iSteel - Conversion of elongation values - Part 1: Carbon and low-alloy steels (ISO 2566-1:2021, Corrected version 2022-06)

This document specifies a method of converting room temperature percentage elongations after
fracture obtained on various proportional and non-proportional gauge lengths to other gauge lengths.
Formula (1), on which conversions are based, is considered to be reliable when applied to carbon,
carbon manganese, molybdenum and chromium molybdenum steels within the tensile strength range
300 N/mm2 to 700 N/mm2 and in the hot-rolled, hot-rolled and normalized or annealed conditions, with
or without tempering.
These conversions are not applicable to:
a) cold reduced steels;
b) quenched and tempered steels;
c) austenitic steels.
These conversions are not applicable when the gauge length exceeds 25 S0 or where the width to
thickness ratio of the test piece exceeds 20.

Stahl - Umrechnung von Bruchdehnungswerten - Teil 1: Unlegierte und niedrig legierte Stähle (ISO 2566-1:2021)

Dieses Dokument legt ein Verfahren für die Umrechnung von prozentualen Dehnungswerten nach erfolgtem Bruch bei Raumtemperatur fest, bei dem Bruchdehnungswerte, die bei verschiedenen proportionalen und nicht-proportionalen Messlängen ermittelt wurden, auf andere Messlängen umgerechnet werden.
Die Gleichung (1), die den Umrechnungen zugrunde liegt, gilt als zuverlässig, wenn sie auf unlegierte Stähle, Kohlenstoff-Mangan-, Molybdän- und Chrom-Molybdän-Stahl im Zugfestigkeitsbereich von 300 N/mm2 bis 700 N/mm2 und im warmgewalzten, warmgewalzten und normalgeglühten oder geglühten Zustand, mit oder ohne Anlassen, angewendet wird.
Diese Umrechnungen sind nicht anwendbar auf:
a) kaltgewalzte Stähle;
b) vergütete Stähle;
c) austenitische Stähle.
Diese Umrechnungen sind nicht anzuwenden, wenn die Messlänge 25√(S_0 ) überschreitet oder das Verhältnis der Probenbreite zur -dicke größer als 20 ist.

Acier - Conversion des valeurs d'allongement - Partie 1: Aciers au carbone et aciers faiblement alliés (ISO 2566-1:2021, Version corrigée 2022-06)

Le présent document spécifie une méthode de conversion entre les valeurs d’allongement pour cent, à température ambiante, après rupture obtenues avec différentes longueurs entre repères, proportionnelles et non proportionnelles, et celles obtenues pour d’autres longueurs entre repères.
La Formule (1), sur laquelle les conversions sont basées, est considérée comme valable lorsqu’elle s’applique aux aciers au carbone, au carbone manganèse, molybdène et chrome molybdène dont la résistance à la traction est comprise entre 300 N/mm2 et 700 N/mm2, à l’état laminé à chaud, laminé à chaud et normalisé ou recuit, avec ou sans revenu.
Ces conversions ne sont pas applicables aux:
a) aciers laminés à froid;
b) aciers trempés et revenus;
c) aciers austénitiques.
Ces conversions ne sont pas applicables lorsque la longueur entre repères est supérieure à  ou lorsque le rapport de la largeur à l’épaisseur de l’éprouvette est supérieur 20.

Jekla - Pretvarjanje vrednosti raztezkov - 1. del: Ogljikova in malolegirana jekla (ISO 2566-1:2021, popravljena različica 2022-06)

Ta dokument določa metodo za pretvarjanje odstotnih raztezkov pri sobni temperaturi ob porušitvi, pridobljenih za različne sorazmerne in nesorazmerne merilne dolžine glede na druge merilne dolžine. Formula (1), na kateri temeljijo pretvorbe, se šteje za zanesljivo, kadar se uporablja za ogljikova, ogljikovo-manganova, molibdenova in krom-molibdenova jekla v območju natezne trdnosti od 300 do 700 N/mm2 ter v vroče valjanem, vroče valjanem in normaliziranem ali žarjenem stanju, s tempranjem ali brez. Te pretvorbe se ne uporabljajo za: a) hladno valjana jekla; b) kaljena in temprana jekla; c) avstenitna jekla. Te pretvorbe se ne uporabljajo, če merilna dolžina presega 25 S0 oziroma je razmerje med širino in debelino preskušanca večje od 20.

General Information

Status
Published
Public Enquiry End Date
10-Oct-2021
Publication Date
07-Mar-2022
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
03-Jan-2022
Due Date
10-Mar-2022
Completion Date
08-Mar-2022

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 2566-1:2022
01-april-2022
Nadomešča:
SIST EN ISO 2566-1:2000
Jekla - Pretvarjanje vrednosti raztezkov - 1. del: Ogljikova in malolegirana jekla
(ISO 2566-1:2021, popravljena različica 2022-06)
iSteel - Conversion of elongation values - Part 1: Carbon and low-alloy steels (ISO 2566-
1:2021, Corrected version 2022-06)
Stahl - Umrechnung von Bruchdehnungswerten - Teil 1: Unlegierte und niedrig legierte
Stähle (ISO 2566-1:2021)
Acier - Conversion des valeurs d'allongement - Partie 1: Aciers au carbone et aciers
faiblement alliés (ISO 2566-1:2021, Version corrigée 2022-06)
Ta slovenski standard je istoveten z: EN ISO 2566-1:2021
ICS:
77.040.10 Mehansko preskušanje kovin Mechanical testing of metals
77.080.20 Jekla Steels
SIST EN ISO 2566-1:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 2566-1:2022

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SIST EN ISO 2566-1:2022


EN ISO 2566-1
EUROPEAN STANDARD

NORME EUROPÉENNE

December 2021
EUROPÄISCHE NORM
ICS 77.040.10 Supersedes EN ISO 2566-1:1999
English Version

Steel - Conversion of elongation values - Part 1: Carbon
and low-alloy steels (ISO 2566-1:2021, Corrected version
2022-06)
Acier - Conversion des valeurs d'allongement - Partie Stahl - Umrechnung von Bruchdehnungswerten - Teil
1: Aciers au carbone et aciers faiblement alliés (ISO 1: Unlegierte und niedrig legierte Stähle (ISO 2566-
2566-1:2021, Version corrigée 2022-06) 1:2021, korrigierte Fassung 2022-06)
This European Standard was approved by CEN on 15 November 2021.

This European Standard was corrected and reissued by the CEN-CENELEC Management Centre on 29 June 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATIO N

E U R O P Ä I SC H E S KOMITEE FÜR NORMUN G

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 2566-1:2021 E
worldwide for CEN national Members.

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SIST EN ISO 2566-1:2022
EN ISO 2566-1:2021 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 2566-1:2022
EN ISO 2566-1:2021 (E)
European foreword
This document (EN ISO 2566-1:2021) has been prepared by Technical Committee ISO/TC 17 "Steel" in
collaboration with Technical Committee CEN/TC 459/SC 1 “Test methods for steel (other than chemical
analysis)” the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by June 2022, and conflicting national standards shall be
withdrawn at the latest by June 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 2566-1:1999.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 2566-1:2021, Corrected version 2022-06 has been approved by CEN as EN ISO 2566-
1:2021 without any modification.


3

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SIST EN ISO 2566-1:2022

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SIST EN ISO 2566-1:2022
INTERNATIONAL ISO
STANDARD 2566-1
Third edition
2021-12
Corrected version
2022-06
Steel — Conversion of elongation
values —
Part 1:
Carbon and low-alloy steels
Acier — Conversion des valeurs d'allongement —
Partie 1: Aciers au carbone et aciers faiblement alliés
Reference number
ISO 2566-1:2021(E)
© ISO 2021

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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2021 – All rights reserved

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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and symbols . 1
3.1 Terms and definitions . 1
3.2 Symbols . 2
4 Basic formula .2
5 Requirements on conversions .2
6 Conversion from one proportional gauge length to another proportional gauge
length . 3
7 Conversion from one non-proportional gauge length to another non-proportional
gauge length for test pieces of equal cross-sectional area. 3
8 Conversion from a non-proportional gauge length to another non-proportional
gauge length for test pieces of different cross-sectional areas .4
9 Conversion from a proportional gauge length to a non-proportional gauge length .4
9.1 General . 4
9.2 Conversion factors from 56, 5 S to non-proportional gauge length . 5
0
9.3 Conversion factors from 4 S to non-proportional gauge length . 8
0
9.4 Elongation values . 10
10 Use of Figures .26
Bibliography .33
iii
© ISO 2021 – All rights reserved

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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 20, General
technical delivery conditions, sampling and mechanical testing methods, in collaboration with the
European Committee for Standardization (CEN) Technical Committee CEN/TC 459/SC 1, Test methods
for steel (other than chemical analysis), in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 2566-1:1984), of which it constitutes a
minor revision. The changes are as follows:
— complete editorial revision;
— Tables 2 to 5 have been renamed due to reordering in order to follow the logical flow of information
of this document;
— Clause 9 has been restructured into four sub-clauses in order to follow the logical flow of information
of this document.
A list of all parts in the ISO 2566 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
This corrected version of ISO 2566-1:2021 incorporates the following corrections:
— two of the values given in Tables 1 and 3 were incorrect: the value "1,960" was replaced with "0,960"
in Table 1 and the value "0,754" was replaced with "0,574" in Table 3.
iv
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Introduction
Several different gauge lengths are commonly in use for the determination of percentage elongation of
steels in tensile testing. Fixed gauge lengths of 50 mm, 80 mm, 100 mm and 200 mm are used;
proportional gauge lengths of kS are also used for flat and round test pieces, where k may be one of
0
a number of values, i.e. 4; 5,65; 8,16 or 11,3.
The value 56, 5 S is adopted as the internationally preferred proportional gauge length.
0
Arising from this choice and the existence of specifications stipulating minimum percentage elongations
on different gauge lengths, a growing need has been evident for an International Standard that could be
used to convert test results into values based on the different gauge lengths. Accordingly, this document
includes tables of conversion factors, tables of actual conversions for some of the most commonly used
gauge lengths and elongation values, and figures which may also be used for such conversions. When
using these conversions, however, note should be taken of the limitations on their applicability, as
stated in Clause 1.
v
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SIST EN ISO 2566-1:2022

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SIST EN ISO 2566-1:2022
INTERNATIONAL STANDARD ISO 2566-1:2021(E)
Steel — Conversion of elongation values —
Part 1:
Carbon and low-alloy steels
1 Scope
This document specifies a method of converting room temperature percentage elongations after
fracture obtained on various proportional and non-proportional gauge lengths to other gauge lengths.
Formula (1), on which conversions are based, is considered to be reliable when applied to carbon,
carbon manganese, molybdenum and chromium molybdenum steels within the tensile strength range
2 2
300 N/mm to 700 N/mm and in the hot-rolled, hot-rolled and normalized or annealed conditions, with
or without tempering.
These conversions are not applicable to:
a) cold reduced steels;
b) quenched and tempered steels;
c) austenitic steels.
These conversions are not applicable when the gauge length exceeds 25 S or where the width to
0
thickness ratio of the test piece exceeds 20.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1.1
gauge length
length of the parallel portion of the test piece used for measurement of strain
Note 1 to entry: The term is hereafter used in this document to denote the original gauge length, L , marked on
0
the test piece for the determination of percentage elongation after fracture, A.
3.1.2
proportional gauge length
gauge length (3.1.1) having a specified relation to the square root of the cross-sectional area, for
example 5,65 S
0
1
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
3.1.3
non-proportional gauge length
gauge length (3.1.1) not specifically related to the cross-sectional area of the test piece, usually
expressed in a given dimension, for example 50 mm
3.2 Symbols
A Percentage elongation after fracture on a gauge length, obtained on test
A Percentage elongation on a different gauge length, required by conversion
r
d Diameter of test piece
L
Original gauge length
0
S
Original cross-sectional area of test piece
0
4 Basic formula
[1]
The data contained in this document are based on the Oliver formula , which is now widely used for
such elongation conversions. The Oliver formula can, in a simplified form, be expressed as Formula (1):
04,
 
S
0
AA=17, 4 (1)
 
r
L
 0 
where
A is the required elongation on gauge length L ;
r 0
A
is the elongation on gauge length of 4 S ;
0
L
is the original gauge length;
0
S
is the original cross-sectional area of test piece.
0
Formula (1) gives a direct conversion of elongation on 4 S to the equivalent for a test piece of cross-
0
sectional area S , and a gauge length L . Expressed in terms of 56, 5 S , which is now regarded as the
0 0 0
internationally accepted standard gauge length, it becomes Formula (2):
04,
 
S
0
AA=2 (2)
 
r
L
 0 
where A is the elongation on gauge length of 56, 5 S .
0
Tables 1 to 21 and Figures 1 to 5 are based on Formulae (1) and (2).
Care should be exercised in the case of strip under 4 mm thickness, as the index in Formulae (1) and (2)
increases with decreasing thickness; the value to be used shall be the subject of agreement between the
customer and the supplier.
5 Requirements on conversions
While, as indicated, the conversions are considered to be reliable within the stated limitations, because
of the various factors influencing the determination of percentage elongations, they shall be used for
acceptance purposes only by agreement between the customer and supplier.
2
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
In cases of dispute, the elongation shall be determined on the gauge length stated in the relevant
specification.
6 Conversion from one proportional gauge length to another proportional gauge
length
Simple multiplying factors based on the formula are used for such conversions, and the relationships
between several of the more widely used proportional gauge lengths are given in Table 1. Detailed
conversions of elongations obtained on 4 S to 56, 5 S are given in Table 2.
0 0
Table 1 — Conversion factors : Proportional gauge length
Factor for conversion to:
Conversion
from: 4d 5d 8d
4 S 56, 5 S 81, 6 S 11,3 S
0 0 0 0
1,000 0,870 0,759 0,661 0,953 0,870 0,721
4 S
0
1,149 1,000 0,863 0,759 1,093 1,000 0,828
56, 5 S
0
1,330 1,158 1,000 0,879 1,268 1,158 0,960
81, 6 S
0
1,514 1,317 1,137 1,000 1,443 1,317 1,091
11,3 S
0
4d 1,050 0,916 0,790 0,694 1,000 0,916 0,758
5d 1,149 1,000 0,863 0,759 1,093 1,000 0,828
8d 1,389 1,207 1,042 0,918 1,319 1,207 1,000
a
Table 2 — Elongation values on 56, 5 S corresponding to those obtained on 4 S gauge
0 0
length
Actual elonga-
Corresponding elongation (%) on 56, 5 S
0
tion (%)
measured on
0 1 2 3 4 5 6 7 8 9
4 S
0
10 9 10 10 11 12 13 14 15 16 17
20 17 18 19 20 21 22 23 23 24 25
30 26 27 28 29 30 30 31 32 33 34
40 35 36 37 37 38 39 40 41 42 43
50 43 44 45 46 47 48 49 50 50 51
a
Factor 0,87. Values rounded to nearest whole number.
7 Conversion from one non-proportional gauge length to another non-
proportional gauge length for test pieces of equal cross-sectional area
The conversion of elongation values of different fixed gauge lengths on test pieces of equal cross-
sectional area are also made by simple factors. Conversion factors for gauge lengths of 50 mm, 80 mm,
100 mm and 200 mm are given in Table 3.
3
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
a
Table 3 — Conversion factors : Non-proportional gauge length
Factor for conversion to:
Conversion from:
50 mm 80 mm 100 mm 200 mm
50 mm 1,000 0,829 0,758 0,574
80 mm 1,207 1,000 0,915 0,693
100 mm 1,320 1,093 1,000 0,758
200 mm 1,741 1,443 1,320 1,000
a
Provided cross-sectional areas are the same.
8 Conversion from a non-proportional gauge length to another non-proportional
gauge length for test pieces of different cross-sectional areas
It is preferable for this calculation to be made in two stages with an initial conversion to 56, 5 S .
0
EXAMPLE
Elongation of 24 % on 200 mm for a 40 mm x 15 mm test piece in terms of equivalent on a
30 mm x 10 mm test piece with gauge lengths equal to 200 mm, 100 mm and 50 mm.
24 x 1/0,863 = 27,8 % on 56, 5 S (see Table 3)
0
27,8 x 0,752 = 20,9 % on 30 mm x 10 mm with 200 mm gauge length
27,8 x 0,992 = 27,6 % on 30 mm x 10 mm with 100 mm gauge length
27,8 x 1,309 = 36,4 % on 30 mm x 10 mm with 50 mm gauge length
Elongation on other proportional gauge lengths can be obtained by using the factors given in Table 1.
9 Conversion from a proportional gauge length to a non-proportional gauge
length
9.1 General
The conversion factors are variable according to the cross-sectional area of the non-proportional test
piece. Table 4 gives the multiplying factors for conversion from elongation on 56, 5 S to the equivalent
0
on fixed gauge lengths of 50 mm, 80 mm, 100 mm and 200 mm for a range of cross-sectional areas. For
conversions in the reverse direction, i.e. elongation on a fixed gauge length to the equivalent of 56, 5 S
0
, the reciprocal of the factors is used.
EXAMPLE

a) Elongation of 20 % on 56, 5 S is equivalent to 20 x 1,139 = 22,78 % on a 25 mm wide test
0
piece of 6 mm thickness with a 50 mm gauge length (see Table 4);
b) Elongation of 25 % on a 40 mm x 10 mm test piece of 200 mm gauge length is equivalent to
25 x 1/0,796 = 31,4 % on 56, 5 S (see Table 4).
0
From the examples shown, it will be seen that conversions involving other proportional gauge lengths
can be obtained by prior or subsequent use of the factors shown in Table 1.
4
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
9.2 Conversion factors from 56, 5 S to non-proportional gauge length
0
Factors shown under “non-proportional gauge lengths” give the value of
04,
 
S
0
2
 
L
 
To convert from values on a gauge length of 56, 5 S to a non-proportional gauge length, multiply by
0
the appropriate factor.
To convert from values on a non-proportional gauge length to 56, 5 S , divide by the appropriate
0
factor.
See also Figures 1 and 2.
Table 4 — Conversion factors from 56, 5 S to non-proportional gauge lengths
0
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
5 0,331 0,437 0,478 0,577
10 0,381 0,502 0,549 0,663
15 0,413 0,545 0,596 0,719
20 0,437 0,577 0,631 0,761
25 0,457 0,603 0,660 0,796
30 0,474 0,626 0,684 0,826
35 0,489 0,645 0,706 0,852
40 0,502 0,663 0,725 0,875
45 0,514 0,679 0,742 0,896
50 0,525 0,693 0,758 0,915
55 0,535 0,706 0,772 0,932
60 0,545 0,719 0,786 0,949
70 0,562 0,741 0,811 0,978
80 0,577 0,761 0,833 1,005
90 0,591 0,780 0,852 1,029
100 0,603 0,796 0,871 1,051
110 0,615 0,812 0,887 1,071
120 0,626 0,826 0,903 1,090
130 0,636 0,839 0,917 1,107
140 0,645 0,852 0,931 1,124
150 0,654 0,863 0,944 1,139
160 0,663 0,875 0,956 1,154
170 0,671 0,885 0,968 1,168
180 0,679 0,896 0,979 1, 182
190 0,686 0,905 0,990 1,195
200 0,693 0,915 1,000 1,207
210 0,700 0,924 1,010 1,219
220 0,706 0,932 1,019 1,230
230 0,713 0,941 1,028 1,241
5
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Table 4 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
240 0,719 0,949 1,037 1,252
250 0,725 0,956 1,046 1,262
260 0,730 0,964 1,054 1,272
270 0,736 0,971 1,062 1,281
280 0,741 0,978 1,070 1,291
290 0,747 0,985 1,077 1,300
300 0,752 0,992 1,084 1,309
310 0,757 0,998 1,092 1,317
320 0,761 1,005 1,099 1,326
330 0,766 1,011 1,105 1,334
340 0,771 1,017 1,112 1,342
350 0,775 1,023 1,118 1,350
360 0,780 1,029 1,125 1,357
370 0,784 1,034 1,131 1,365
380 0,788 1,040 1,137 1,372
390 0,792 1,045 1,143 1,379
400 0,796 1,051 1,149 1,386
410 0,800 1,056 1,154 1,393
420 0,804 1,061 1,160 1,400
430 0,808 1,066 1,165 1,406
440 0,812 1,071 1,171 1,413
450 0,815 1,076 1,176 1,419
460 0,819 1,080 1,181 1,426
470 0,822 1,085 1,186 1,432
480 0,826 1,090 1,191 1,438
490 0,829 1,094 1,196 1,444
500 0,833 1,099 1,201 1,450
550 0,849 1,120 1,224 1,477
600 0,863 1,139 1,246 1,503
650 0,877 1,158 1,266 1,528
700 0,891 1,175 1,285 1,550
750 0,903 1,191 1,303 1,572
800 0,915 1,207 1,320 1,592
850 0,926 1,222 1,336 1,612
900 0,936 1,236 1,351 1,630
950 0,947 1,249 1,366 1,648
1 000 0,956 1,262 1,380 1,665
1 050 0,966 1,274 1,393 1,681
1 100 0,975 1,286 1,406 1,697
1 150 0,983 1,298 1,419 1,712
1 200 0,992 1,309 1,431 1,727
1 250 1,000 1,320 1,443 1,741
6
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Table 4 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
1 300 1,008 1,330 1,454 1,755
1 350 1,016 1,340 1,465 1,768
1 400 1,023 1,350 1,476 1,781
1 450 1,030 1,359 1,486 1,794
1 500 1,037 1,369 1,496 1,806
1 550 1,044 1,378 1,506 1,818
1 600 1,051 1,386 1,516 1,829
1 650 1,057 1,395 1,525 1,841
1 700 1,063 1,403 1,534 1,852
1 750 1,070 1,411 1,543 1,862
1 800 1,076 1,419 1,552 1,873
1 850 1,082 1,427 1,560 1,883
1 900 1,087 1,435 1,569 1,893
1 950 1,093 1,442 1,577 1,903
2 000 1,099 1,450 1,585 1,913
2 050 1,104 1,457 1,593 1,922
2 100 1,109 1,464 1,600 1,931
2 150 1,115 1,471 1,608 1,941
2 200 1,120 1,477 1,615 1,950
2 250 1,125 1,484 1,623 1,958
2 300 1,130 1,491 1,630 1,967
2 350 1,135 1,497 1,637 1,975
2 400 1,139 1,503 1,644 1,984
2 450 1,144 1,510 1,651 1,992
2 500 1,149 1,516 1,657 2,000
2 550 1,153 1,522 1,664 2,008
2 600 1,158 1,528 1,670 2,016
2 650 1,162 1,533 1,677 2,023
2 700 1,167 1,539 1,683 2,031
2 750 1,171 1,545 1,689 2,038
2 800 1,175 1,550 1,695 2,046
2 850 1,179 1,556 1,701 2,053
2 900 1,183 1,561 1,707 2,060
2 950 1,187 1,567 1,713 2,067
3 000 1,191 1,572 1,719 2,074
7
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
9.3 Conversion factors from 4 S to non-proportional gauge length
0
Factors shown under “non-proportional gauge length” give the value of
04,
 
S
0
17, 4
 
L
 
To convert from values on a gauge length of 4 S to a non-proportional gauge length, multiply by the
0
appropriate factor.
To convert from values on a non-proportional gauge length to 4 S , divide by the appropriate factor.
0
See also Figures 3 and 4.
Table 5 — Conversion factors from 4 S to non-proportional gauge length
0
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
5 0,288 0,380 0,416 0,502
10 0,331 0,437 0,478 0,577
15 0,359 0,474 0,518 0,625
20 0,380 0,502 0,549 0,662
25 0,398 0,525 0,574 0,693
30 0,413 0,544 0,595 0,718
35 0,426 0,562 0,614 0,741
40 0,437 0,577 0,631 0,761
45 0,447 0,590 0,646 0,779
50 0,457 0,603 0,659 0,796
55 0,466 0,615 0,672 0,811
60 0,474 0;625 0,684 0,825
70 0,489 0,645 0,705 0,851
80 0,502 0,662 0,724 0,874
90 0,514 0,678 0,742 0,895
100 0,525 0,693 0,757 0,914
110 0,535 0,706 0,772 0,932
120 0,544 0,718 0,786 0,948
130 0,553 0,730 0,798 0,963
140 0,562 0,741 0,810 0,978
150 0,560 0,751 0,821 0,991
160 0,577 0,761 0,832 1,004
170 0,584 0,770 0,642 1,016
180 0,590 0,779 0,852 1,028
190 0,597 0,788 0,861 1,039
200 0,603 0,796 0,870 1,050
210 0,609 0,804 0,879 1,060
220 0,615 0,811 0,887 1,070
230 0,620 0,818 0,895 1,080
240 0,625 0,825 0,902 1,089
8
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Table 5 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
250 0,631 0,832 0,910 1,098
260 0,636 0,839 0,917 1,107
270 0,640 0,845 0,924 1,115
280 0,645 0,851 0,931 1,123
290 0,650 0,857 0,937 1,131
300 0,654 0,863 0,943 1,139
310 0,658 0,869 0,950 1,146
320 0,662 0,874 0,956 1,153
330 0,667 0,880 0,962 1,161
340 0,671 0,885 0,967 1,168
350 0,674 0,890 0,973 1,174
360 0,678 0,895 0,979 1,181
370 0,682 0,900 0,984 1,187
380 0,686 0, 905 0,98
...

SLOVENSKI STANDARD
SIST EN ISO 2566-1:2022
01-april-2022
Nadomešča:
SIST EN ISO 2566-1:2000
Jekla - Pretvarjanje vrednosti raztezkov - 1. del: Ogljikova in malolegirana jekla
(ISO 2566-1:2021)
Steel - Conversion of elongation values - Part 1: Carbon and low alloy steels (ISO 2566-
1:2021)
Stahl - Umrechnung von Bruchdehnungswerten - Teil 1: Unlegierte und niedrig legierte
Stähle (ISO 2566-1:2021)
Acier - Conversion des valeurs d'allongement - Partie 1: Aciers au carbone et aciers
faiblement alliés (ISO 2566-1:2021)
Ta slovenski standard je istoveten z: EN ISO 2566-1:2021
ICS:
77.040.10 Mehansko preskušanje kovin Mechanical testing of metals
77.080.20 Jekla Steels
SIST EN ISO 2566-1:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 2566-1:2022

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SIST EN ISO 2566-1:2022


EN ISO 2566-1
EUROPEAN STANDARD

NORME EUROPÉENNE

December 2021
EUROPÄISCHE NORM
ICS 77.040.10 Supersedes EN ISO 2566-1:1999
English Version

Steel - Conversion of elongation values - Part 1: Carbon
and low-alloy steels (ISO 2566-1:2021)
Acier - Conversion des valeurs d'allongement - Partie Stahl - Umrechnung von Bruchdehnungswerten - Teil
1: Aciers au carbone et aciers faiblement alliés (ISO 1: Unlegierte und niedrig legierte Stähle (ISO 2566-
2566-1:2021) 1:2021)
This European Standard was approved by CEN on 15 November 2021.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 2566-1:2021 E
worldwide for CEN national Members.

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SIST EN ISO 2566-1:2022
EN ISO 2566-1:2021 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 2566-1:2022
EN ISO 2566-1:2021 (E)
European foreword
This document (EN ISO 2566-1:2021) has been prepared by Technical Committee ISO/TC 17 "Steel" in
collaboration with Technical Committee CEN/TC 459/SC 1 “Test methods for steel (other than chemical
analysis)” the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by June 2022, and conflicting national standards shall be
withdrawn at the latest by June 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 2566-1:1999.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 2566-1:2021 has been approved by CEN as EN ISO 2566-1:2021 without any
modification.


3

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SIST EN ISO 2566-1:2022

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SIST EN ISO 2566-1:2022
INTERNATIONAL ISO
STANDARD 2566-1
Third edition
2021-12
Steel — Conversion of elongation
values —
Part 1:
Carbon and low-alloy steels
Acier — Conversion des valeurs d'allongement —
Partie 1: Aciers au carbone et aciers faiblement alliés
Reference number
ISO 2566-1:2021(E)
© ISO 2021

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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and symbols . 1
3.1 Terms and definitions . 1
3.2 Symbols . 2
4 Basic formula .2
5 Requirements on conversions .2
6 Conversion from one proportional gauge length to another proportional gauge
length . 3
7 Conversion from one non-proportional gauge length to another non-proportional
gauge length for test pieces of equal cross-sectional area. 3
8 Conversion from a non-proportional gauge length to another non-proportional
gauge length for test pieces of different cross-sectional areas .4
9 Conversion from a proportional gauge length to a non-proportional gauge length .4
9.1 General . 4
9.2 Conversion factors from to non-proportional gauge length . 5
9.3 Conversion factors from to non-proportional gauge length . 8
9.4 Elongation values . 10
10 Use of Figures .26
Bibliography .33
iii
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 20, General
technical delivery conditions, sampling and mechanical testing methods, in collaboration with the
European Committee for Standardization (CEN) Technical Committee CEN/TC 459/SC 1, Test methods
for steel (other than chemical analysis), in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 2566-1:1984), of which it constitutes a
minor revision. The changes are as follows:
— complete editorial revision;
— Tables 2 to 5 have been renamed due to reordering in order to follow the logical flow of information
of this document;
— Clause 9 has been restructured into four sub-clauses in order to follow the logical flow of information
of this document.
A list of all parts in the ISO 2566 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Introduction
Several different gauge lengths are commonly in use for the determination of percentage elongation of
steels in tensile testing. Fixed gauge lengths of 50 mm, 80 mm, 100 mm and 200 mm are used;
proportional gauge lengths of kS are also used for flat and round test pieces, where k may be one of
0
a number of values, i.e. 4; 5,65; 8,16 or 11,3.
The value 56, 5 S is adopted as the internationally preferred proportional gauge length.
0
Arising from this choice and the existence of specifications stipulating minimum percentage elongations
on different gauge lengths, a growing need has been evident for an International Standard that could be
used to convert test results into values based on the different gauge lengths. Accordingly, this document
includes tables of conversion factors, tables of actual conversions for some of the most commonly used
gauge lengths and elongation values, and figures which may also be used for such conversions. When
using these conversions, however, note should be taken of the limitations on their applicability, as
stated in Clause 1.
v
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SIST EN ISO 2566-1:2022

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SIST EN ISO 2566-1:2022
INTERNATIONAL STANDARD ISO 2566-1:2021(E)
Steel — Conversion of elongation values —
Part 1:
Carbon and low-alloy steels
1 Scope
This document specifies a method of converting room temperature percentage elongations after
fracture obtained on various proportional and non-proportional gauge lengths to other gauge lengths.
Formula (1), on which conversions are based, is considered to be reliable when applied to carbon,
carbon manganese, molybdenum and chromium molybdenum steels within the tensile strength range
2 2
300 N/mm to 700 N/mm and in the hot-rolled, hot-rolled and normalized or annealed conditions, with
or without tempering.
These conversions are not applicable to:
a) cold reduced steels;
b) quenched and tempered steels;
c) austenitic steels.
These conversions are not applicable when the gauge length exceeds 25 S or where the width to
0
thickness ratio of the test piece exceeds 20.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1.1
gauge length
length of the parallel portion of the test piece used for measurement of strain
Note 1 to entry: The term is hereafter used in this document to denote the original gauge length, L , marked on
0
the test piece for the determination of percentage elongation after fracture, A.
3.1.2
proportional gauge length
gauge length (3.1.1) having a specified relation to the square root of the cross-sectional area, for
example 5,65 S
0
1
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
3.1.3
non-proportional gauge length
gauge length (3.1.1) not specifically related to the cross-sectional area of the test piece, usually
expressed in a given dimension, for example 50 mm
3.2 Symbols
A Percentage elongation after fracture on a gauge length, obtained on test
A Percentage elongation on a different gauge length, required by conversion
r
d Diameter of test piece
L
Original gauge length
0
S
Original cross-sectional area of test piece
0
4 Basic formula
[1]
The data contained in this document are based on the Oliver formula , which is now widely used for
such elongation conversions. The Oliver formula can, in a simplified form, be expressed as Formula (1):
04,
 
S
0
AA=17, 4 (1)
 
r
L
 0 
where
A is the required elongation on gauge length L ;
r 0
A
is the elongation on gauge length of 4 S ;
0
L
is the original gauge length;
0
S
is the original cross-sectional area of test piece.
0
Formula (1) gives a direct conversion of elongation on 4 S to the equivalent for a test piece of cross-
0
sectional area S , and a gauge length L . Expressed in terms of 56, 5 S , which is now regarded as the
0 0 0
internationally accepted standard gauge length, it becomes Formula (2):
04,
 
S
0
AA=2 (2)
 
r
L
 0 
where A is the elongation on gauge length of 56, 5 S .
0
Tables 1 to 21 and Figures 1 to 5 are based on Formulae (1) and (2).
Care should be exercised in the case of strip under 4 mm thickness, as the index in Formulae (1) and (2)
increases with decreasing thickness; the value to be used shall be the subject of agreement between the
customer and the supplier.
5 Requirements on conversions
While, as indicated, the conversions are considered to be reliable within the stated limitations, because
of the various factors influencing the determination of percentage elongations, they shall be used for
acceptance purposes only by agreement between the customer and supplier.
2
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
In cases of dispute, the elongation shall be determined on the gauge length stated in the relevant
specification.
6 Conversion from one proportional gauge length to another proportional gauge
length
Simple multiplying factors based on the formula are used for such conversions, and the relationships
between several of the more widely used proportional gauge lengths are given in Table 1. Detailed
conversions of elongations obtained on 4 S to 56, 5 S are given in Table 2.
0 0
Table 1 — Conversion factors : Proportional gauge length
Factor for conversion to:
Conversion
from: 4d 5d 8d
4 S 56, 5 S 81, 6 S 11,3 S
0 0 0 0
1,000 0,870 0,759 0,661 0,953 0,870 0,721
4 S
0
1,149 1,000 0,863 0,759 1,093 1,000 0,828
56, 5 S
0
1,330 1,158 1,000 0,879 1,268 1,158 1,960
81, 6 S
0
1,514 1,317 1,137 1,000 1,443 1,317 1,091
11,3 S
0
4d 1,050 0,916 0,790 0,694 1,000 0,916 0,758
5d 1,149 1,000 0,863 0,759 1,093 1,000 0,828
8d 1,389 1,207 1,042 0,918 1,319 1,207 1,000
a
Table 2 — Elongation values on 56, 5 S corresponding to those obtained on 4 S gauge
0 0
length
Actual elonga-
Corresponding elongation (%) on 56, 5 S
0
tion (%)
measured on
0 1 2 3 4 5 6 7 8 9
4 S
0
10 9 10 10 11 12 13 14 15 16 17
20 17 18 19 20 21 22 23 23 24 25
30 26 27 28 29 30 30 31 32 33 34
40 35 36 37 37 38 39 40 41 42 43
50 43 44 45 46 47 48 49 50 50 51
a
Factor 0,87. Values rounded to nearest whole number.
7 Conversion from one non-proportional gauge length to another non-
proportional gauge length for test pieces of equal cross-sectional area
The conversion of elongation values of different fixed gauge lengths on test pieces of equal cross-
sectional area are also made by simple factors. Conversion factors for gauge lengths of 50 mm, 80 mm,
100 mm and 200 mm are given in Table 3.
3
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
a
Table 3 — Conversion factors : Non-proportional gauge length
Factor for conversion to:
Conversion from:
50 mm 80 mm 100 mm 200 mm
50 mm 1,000 0,829 0,758 0,754
80 mm 1,207 1,000 0,915 0,693
100 mm 1,320 1,093 1,000 0,758
200 mm 1,741 1,443 1,320 1,000
a
Provided cross-sectional areas are the same.
8 Conversion from a non-proportional gauge length to another non-proportional
gauge length for test pieces of different cross-sectional areas
It is preferable for this calculation to be made in two stages with an initial conversion to 56, 5 S .
0
EXAMPLE
Elongation of 24 % on 200 mm for a 40 mm x 15 mm test piece in terms of equivalent on a
30 mm x 10 mm test piece with gauge lengths equal to 200 mm, 100 mm and 50 mm.
24 x 1/0,863 = 27,8 % on 56, 5 S (see Table 3)
0
27,8 x 0,752 = 20,9 % on 30 mm x 10 mm with 200 mm gauge length
27,8 x 0,992 = 27,6 % on 30 mm x 10 mm with 100 mm gauge length
27,8 x 1,309 = 36,4 % on 30 mm x 10 mm with 50 mm gauge length
Elongation on other proportional gauge lengths can be obtained by using the factors given in Table 1.
9 Conversion from a proportional gauge length to a non-proportional gauge
length
9.1 General
The conversion factors are variable according to the cross-sectional area of the non-proportional test
piece. Table 4 gives the multiplying factors for conversion from elongation on 56, 5 S to the equivalent
0
on fixed gauge lengths of 50 mm, 80 mm, 100 mm and 200 mm for a range of cross-sectional areas. For
conversions in the reverse direction, i.e. elongation on a fixed gauge length to the equivalent of 56, 5 S
0
, the reciprocal of the factors is used.
EXAMPLE

a) Elongation of 20 % on 56, 5 S is equivalent to 20 x 1,139 = 22,78 % on a 25 mm wide test
0
piece of 6 mm thickness with a 50 mm gauge length (see Table 4);
b) Elongation of 25 % on a 40 mm x 10 mm test piece of 200 mm gauge length is equivalent to
25 x 1/0,796 = 31,4 % on 56, 5 S (see Table 4).
0
From the examples shown, it will be seen that conversions involving other proportional gauge lengths
can be obtained by prior or subsequent use of the factors shown in Table 1.
4
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
9.2 Conversion factors from 56, 5 S to non-proportional gauge length
0
Factors shown under “non-proportional gauge lengths” give the value of
04,
 
S
0
2
 
L
 
To convert from values on a gauge length of 56, 5 S to a non-proportional gauge length, multiply by
0
the appropriate factor.
To convert from values on a non-proportional gauge length to 56, 5 S , divide by the appropriate
0
factor.
See also Figures 1 and 2.
Table 4 — Conversion factors from 56, 5 S to non-proportional gauge lengths
0
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
5 0,331 0,437 0,478 0,577
10 0,381 0,502 0,549 0,663
15 0,413 0,545 0,596 0,719
20 0,437 0,577 0,631 0,761
25 0,457 0,603 0,660 0,796
30 0,474 0,626 0,684 0,826
35 0,489 0,645 0,706 0,852
40 0,502 0,663 0,725 0,875
45 0,514 0,679 0,742 0,896
50 0,525 0,693 0,758 0,915
55 0,535 0,706 0,772 0,932
60 0,545 0,719 0,786 0,949
70 0,562 0,741 0,811 0,978
80 0,577 0,761 0,833 1,005
90 0,591 0,780 0,852 1,029
100 0,603 0,796 0,871 1,051
110 0,615 0,812 0,887 1,071
120 0,626 0,826 0,903 1,090
130 0,636 0,839 0,917 1,107
140 0,645 0,852 0,931 1,124
150 0,654 0,863 0,944 1,139
160 0,663 0,875 0,956 1,154
170 0,671 0,885 0,968 1,168
180 0,679 0,896 0,979 1, 182
190 0,686 0,905 0,990 1,195
200 0,693 0,915 1,000 1,207
210 0,700 0,924 1,010 1,219
220 0,706 0,932 1,019 1,230
230 0,713 0,941 1,028 1,241
5
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Table 4 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
240 0,719 0,949 1,037 1,252
250 0,725 0,956 1,046 1,262
260 0,730 0,964 1,054 1,272
270 0,736 0,971 1,062 1,281
280 0,741 0,978 1,070 1,291
290 0,747 0,985 1,077 1,300
300 0,752 0,992 1,084 1,309
310 0,757 0,998 1,092 1,317
320 0,761 1,005 1,099 1,326
330 0,766 1,011 1,105 1,334
340 0,771 1,017 1,112 1,342
350 0,775 1,023 1,118 1,350
360 0,780 1,029 1,125 1,357
370 0,784 1,034 1,131 1,365
380 0,788 1,040 1,137 1,372
390 0,792 1,045 1,143 1,379
400 0,796 1,051 1,149 1,386
410 0,800 1,056 1,154 1,393
420 0,804 1,061 1,160 1,400
430 0,808 1,066 1,165 1,406
440 0,812 1,071 1,171 1,413
450 0,815 1,076 1,176 1,419
460 0,819 1,080 1,181 1,426
470 0,822 1,085 1,186 1,432
480 0,826 1,090 1,191 1,438
490 0,829 1,094 1,196 1,444
500 0,833 1,099 1,201 1,450
550 0,849 1,120 1,224 1,477
600 0,863 1,139 1,246 1,503
650 0,877 1,158 1,266 1,528
700 0,891 1,175 1,285 1,550
750 0,903 1,191 1,303 1,572
800 0,915 1,207 1,320 1,592
850 0,926 1,222 1,336 1,612
900 0,936 1,236 1,351 1,630
950 0,947 1,249 1,366 1,648
1 000 0,956 1,262 1,380 1,665
1 050 0,966 1,274 1,393 1,681
1 100 0,975 1,286 1,406 1,697
1 150 0,983 1,298 1,419 1,712
1 200 0,992 1,309 1,431 1,727
1 250 1,000 1,320 1,443 1,741
6
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Table 4 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
1 300 1,008 1,330 1,454 1,755
1 350 1,016 1,340 1,465 1,768
1 400 1,023 1,350 1,476 1,781
1 450 1,030 1,359 1,486 1,794
1 500 1,037 1,369 1,496 1,806
1 550 1,044 1,378 1,506 1,818
1 600 1,051 1,386 1,516 1,829
1 650 1,057 1,395 1,525 1,841
1 700 1,063 1,403 1,534 1,852
1 750 1,070 1,411 1,543 1,862
1 800 1,076 1,419 1,552 1,873
1 850 1,082 1,427 1,560 1,883
1 900 1,087 1,435 1,569 1,893
1 950 1,093 1,442 1,577 1,903
2 000 1,099 1,450 1,585 1,913
2 050 1,104 1,457 1,593 1,922
2 100 1,109 1,464 1,600 1,931
2 150 1,115 1,471 1,608 1,941
2 200 1,120 1,477 1,615 1,950
2 250 1,125 1,484 1,623 1,958
2 300 1,130 1,491 1,630 1,967
2 350 1,135 1,497 1,637 1,975
2 400 1,139 1,503 1,644 1,984
2 450 1,144 1,510 1,651 1,992
2 500 1,149 1,516 1,657 2,000
2 550 1,153 1,522 1,664 2,008
2 600 1,158 1,528 1,670 2,016
2 650 1,162 1,533 1,677 2,023
2 700 1,167 1,539 1,683 2,031
2 750 1,171 1,545 1,689 2,038
2 800 1,175 1,550 1,695 2,046
2 850 1,179 1,556 1,701 2,053
2 900 1,183 1,561 1,707 2,060
2 950 1,187 1,567 1,713 2,067
3 000 1,191 1,572 1,719 2,074
7
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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
9.3 Conversion factors from 4 S to non-proportional gauge length
0
Factors shown under “non-proportional gauge length” give the value of
04,
 
S
0
17, 4
 
L
 
To convert from values on a gauge length of 4 S to a non-proportional gauge length, multiply by the
0
appropriate factor.
To convert from values on a non-proportional gauge length to 4 S , divide by the appropriate factor.
0
See also Figures 3 and 4.
Table 5 — Conversion factors from 4 S to non-proportional gauge length
0
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
5 0,288 0,380 0,416 0,502
10 0,331 0,437 0,478 0,577
15 0,359 0,474 0,518 0,625
20 0,380 0,502 0,549 0,662
25 0,398 0,525 0,574 0,693
30 0,413 0,544 0,595 0,718
35 0,426 0,562 0,614 0,741
40 0,437 0,577 0,631 0,761
45 0,447 0,590 0,646 0,779
50 0,457 0,603 0,659 0,796
55 0,466 0,615 0,672 0,811
60 0,474 0;625 0,684 0,825
70 0,489 0,645 0,705 0,851
80 0,502 0,662 0,724 0,874
90 0,514 0,678 0,742 0,895
100 0,525 0,693 0,757 0,914
110 0,535 0,706 0,772 0,932
120 0,544 0,718 0,786 0,948
130 0,553 0,730 0,798 0,963
140 0,562 0,741 0,810 0,978
150 0,560 0,751 0,821 0,991
160 0,577 0,761 0,832 1,004
170 0,584 0,770 0,642 1,016
180 0,590 0,779 0,852 1,028
190 0,597 0,788 0,861 1,039
200 0,603 0,796 0,870 1,050
210 0,609 0,804 0,879 1,060
220 0,615 0,811 0,887 1,070
230 0,620 0,818 0,895 1,080
240 0,625 0,825 0,902 1,089
8
  © ISO 2021 – All rights reserved

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SIST EN ISO 2566-1:2022
ISO 2566-1:2021(E)
Table 5 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
250 0,631 0,832 0,910 1,098
260 0,636 0,839 0,917 1,107
270 0,640 0,845 0,924 1,115
280 0,645 0,851 0,931 1,123
290 0,650 0,857 0,937 1,131
300 0,654 0,863 0,943 1,139
310 0,658 0,869 0,950 1,146
320 0,662 0,874 0,956 1,153
330 0,667 0,880 0,962 1,161
340 0,671 0,885 0,967 1,168
350 0,674 0,890 0,973 1,174
360 0,678 0,895 0,979 1,181
370 0,682 0,900 0,984 1,187
380 0,686 0, 905 0,989 1,194
390 0,689 0,909 0,994 1,200
400 0,693 0,914 0,999 1,206
410 0,696 0,919 1,004 1,212
420 0,699 0,923 1,009 1,218
430 0,703 0,927 1,014 1,224
440 0,706 0,932 1,019 1,229
450 0,709 0,936 l,023 1,235
460 0,712 0,940 1,028 1,240
470 0,715 0,944 1,032 1,246
480 0,718 0,948 1,036 1,251
490 0,721 0,952 1,041 1,256
500 0,724 0,956 1,045 1,261
550 0,738 0,974 1,065 1,285
600 0,751 0,991 1,084 1,308
650 0,763 1,007 1,101 1,329
700 0,775 1,022 1,118 1,349
750 0,786 1,036 1,133 1,368
800 0,796 1,050 1,148 1,385
850 0,805 1,063 1,162 1,402
900 0,815 1,075 1,175 1,418
950 0,824 1
...

SLOVENSKI STANDARD
oSIST prEN ISO 2566-1:2021
01-oktober-2021
Jekla - Pretvarjanje vrednosti raztezkov - 1. del: Ogljikova in malolegirana jekla
(ISO/FDIS 2566-1:2021)
Steel - Conversion of elongation values - Part 1: Carbon and low alloy steels (ISO/FDIS
2566-1:2021)
Stahl - Umrechnung von Bruchdehnungswerten - Teil 1: Unlegierte und niedrig legierte
Stähle (ISO/FDIS 2566-1:2021)
Acier - Conversion des valeurs d'allongement - Partie 1: Aciers au carbone et aciers
faiblement alliés (ISO/FDIS 2566-1:2021)
Ta slovenski standard je istoveten z: prEN ISO 2566-1
ICS:
77.040.10 Mehansko preskušanje kovin Mechanical testing of metals
77.080.20 Jekla Steels
oSIST prEN ISO 2566-1:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 2566-1:2021

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oSIST prEN ISO 2566-1:2021
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 2566-1
ISO/TC 17/SC 20
Steel — Conversion of elongation
Secretariat: SIS
values —
Voting begins on:
2021-07-22
Part 1:
Voting terminates on:
Carbon and low alloy steels
2021-10-14
Acier — Conversion des valeurs d'allongement —
Partie 1: Aciers au carbone et aciers faiblement alliés
ISO/CEN PARALLEL PROCESSING
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 2566-1:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
©
NATIONAL REGULATIONS. ISO 2021

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and symbols . 1
3.1 Terms and definitions . 1
3.2 Symbols . 2
4 Basic formula . 2
5 Requirements on conversions . 2
6 Conversion from one proportional gauge length to another proportional gauge length .3
7 Conversion from one non-proportional gauge length to another non-proportional
gauge length for test pieces of equal cross-sectional area . 3
8 Conversion from a non-proportional gauge length to another non-proportional
gauge length for test pieces of different cross-sectional areas . 4
9 Conversion from a proportional gauge length to a non-proportional gauge length .4
9.1 General . 4
9.2 Conversion factors from 56, 5 S to non-proportional gauge length . 5
0
9.3 Conversion factors from 4 S to non-proportional gauge length . 8
0
9.4 Elongation values .10
10 Use of Figures .26
Bibliography .33
© ISO 2021 – All rights reserved iii

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 20, General
technical delivery conditions, sampling and mechanical testing methods, in collaboration with the
European Committee for Standardization (CEN) Technical Committee CEN/TC 459/SC 1, Test methods
for steel (other than chemical analysis), in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 2566-1:1984), of which it constitutes a
minor revision. The changes compared to the previous edition are as follows:
— complete editorial revision;
— Tables 2 to 5 have been renamed due to reordering in order to follow the logical flow of information
of this document;
— Clause 8 has been restructured into four sub-clauses in order to follow the logical flow of information
of this document.
A list of all parts in the ISO 2566 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

Introduction
Several different gauge lengths are commonly in use for the determination of percentage elongation of
steels in tensile testing. Fixed gauge lengths of 50 mm, 80 mm, 100 mm and 200 mm are used;
proportional gauge lengths of kS are also used for flat and round test pieces, where k may be one of
0
a number of values, i.e. 4; 5,65; 8,16 or 11,3.
The value 56, 5 S is adopted as the internationally preferred proportional gauge length.
0
Arising from this choice and the existence of specifications stipulating minimum percentage elongations
on different gauge lengths, a growing need has been evident for an International Standard that could be
used to convert test results into values based on the different gauge lengths. Accordingly, this document
includes tables of conversion factors, tables of actual conversions for some of the most commonly used
gauge lengths and elongation values, and figures which may also be used for such conversions. When
using these conversions, however, note should be taken of the limitations on their applicability, as
stated in Clause 1.
© ISO 2021 – All rights reserved v

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oSIST prEN ISO 2566-1:2021

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oSIST prEN ISO 2566-1:2021
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 2566-1:2021(E)
Steel — Conversion of elongation values —
Part 1:
Carbon and low alloy steels
1 Scope
This document specifies a method of converting room temperature percentage elongations after
fracture obtained on various proportional and non-proportional gauge lengths to other gauge lengths.
Formula (1), on which conversions are based, is considered to be reliable when applied to carbon,
carbon manganese, molybdenum and chromium molybdenum steels within the tensile strength range
2
300 to 700 N/mm and in the hot-rolled, hot-rolled and normalized or annealed conditions, with or
without tempering.
These conversions are not applicable to:
a) cold reduced steels;
b) quenched and tempered steels;
c) austenitic steels.
These conversions are not applicable when the gauge length exceeds 25 S or where the width to
0
thickness ratio of the test piece exceeds 20.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1.1
gauge length
length of the parallel portion of the test piece used for measurement of strain
Note 1 to entry: The term is hereafter used in this document to denote the original gauge length, L , marked on
0
the test piece for the determination of percentage elongation after fracture, A.
3.1.2
proportional gauge length
gauge length (3.1.1) having a specified relation to the square root of the cross-sectional area, for
example 5,65 S
0
© ISO 2021 – All rights reserved 1

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

3.1.3
non-proportional gauge length
gauge length (3.1.1) not specifically related to the cross-sectional area of the test piece, usually
expressed in a given dimension, for example 50 mm
3.2 Symbols
A Percentage elongation after fracture on a gauge length, obtained on test
A Percentage elongation on a different gauge length, required by conversion
r
d Diameter of test piece
L
Original gauge length
0
S
Original cross-sectional area of test piece
0
4 Basic formula
[1]
The data contained in this document are based on the Oliver formula , which is now widely used for
such elongation conversions. The Oliver formula can, in a simplified form, be expressed as Formula (1):
04,
 
S
0
AA=17, 4 (1)
 
r
L
 0 
where
A is the required elongation on gauge length L ;
r 0
A
is the elongation on gauge length of 4 S ;
0
L
is the original gauge length;
0
S
is the original cross-sectional area of test piece.
0
Formula (1) gives a direct conversion of elongation on 4 S to the equivalent for a test piece of cross-
0
sectional area S , and a gauge length L . Expressed in terms of 56, 5 S , which is now regarded as the
0 0 0
internationally accepted standard gauge length, it becomes Formula (2):
04,
 
S
0
AA=2 (2)
 
r
L
 0 
where A is the elongation on gauge length of 56, 5 S .
0
Tables 1 to 21 and Figures 1 to 5 are based on Formulae (1) and (2).
Care should be exercised in the case of strip under 4 mm thickness, as the index in Formulae (1) and (2)
increases with decreasing thickness; the value to be used shall be the subject of agreement between the
customer and the supplier.
5 Requirements on conversions
While, as indicated, the conversions are considered to be reliable within the stated limitations, because
of the various factors influencing the determination of percentage elongations, they shall be used for
acceptance purposes only by agreement between the customer and supplier.
2 © ISO 2021 – All rights reserved

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

In cases of dispute, the elongation shall be determined on the gauge length stated in the relevant
specification.
6 Conversion from one proportional gauge length to another proportional gauge
length
Simple multiplying factors based on the formula are used for such conversions, and the relationships
between several of the more widely used proportional gauge lengths are given in Table 1. Detailed
conversions of elongations obtained on 4 S to 56, 5 S are given in Table 2.
0 0
Table 1 — Conversion factors : Proportional gauge length
Factor for conversion to:
Conversion
from: 4d 5d 8d
4 S 56, 5 S 81, 6 S 11,3 S
0 0 0 0
1,000 0,870 0,759 0,661 0,953 0,870 0,721
4 S
0
1,149 1,000 0,863 0,759 1,093 1,000 0,828
56, 5 S
0
1,330 1,158 1,000 0,879 1,268 1,158 1,960
81, 6 S
0
1,514 1,317 1,137 1,000 1,443 1,317 1,091
11,3 S
0
4d 1,050 0,916 0,790 0,694 1,000 0,916 0,758
5d 1,149 1,000 0,863 0,759 1,093 1,000 0,828
8d 1,389 1,207 1,042 0,918 1,319 1,207 1,000
a
Table 2 — Elongation values on 56, 5 S corresponding to those obtained on 4 S gauge
0 0
length
Actual elonga-
Corresponding elongation (%) on 56, 5 S
0
tion (%)
measured on
0 1 2 3 4 5 6 7 8 9
4 S
0
10 9 10 10 11 12 13 14 15 16 17
20 17 18 19 20 21 22 23 23 24 25
30 26 27 28 29 30 30 31 32 33 34
40 35 36 37 37 38 39 40 41 42 43
50 43 44 45 46 47 48 49 50 50 51
a
Factor 0,87. Values rounded to nearest whole number.
7 Conversion from one non-proportional gauge length to another non-
proportional gauge length for test pieces of equal cross-sectional area
The conversion of elongation values of different fixed gauge lengths on test pieces of equal cross-
sectional area are also made by simple factors. Conversion factors for gauge lengths of 50 mm, 80 mm,
100 mm and 200 mm are given in Table 3.
© ISO 2021 – All rights reserved 3

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

a
Table 3 — Conversion factors : Non-proportional gauge length
Factor for conversion to:
Conversion from:
50 mm 80 mm 100 mm 200 mm
50 mm 1,000 0,829 0,758 0,754
80 mm 1,207 1,000 0,915 0,693
100 mm 1,320 1,093 1,000 0,758
200 mm 1,741 1,443 1,320 1,000
a
Provided cross-sectional areas are the same.
8 Conversion from a non-proportional gauge length to another non-proportional
gauge length for test pieces of different cross-sectional areas
It is preferable for this calculation to be made in two stages with an initial conversion to 56, 5 S .
0
EXAMPLE
Elongation of 24 % on 200 mm for a 40 mm x 15 mm test piece in terms of equivalent on a
30 mm x 10 mm test piece with gauge lengths equal to 200 mm, 100 mm and 50 mm.
24 x 1/0,863 = 27,8 % on 56, 5 S (see Table 3).
0
27,8 x 0,752 = 20,9 % on 30 mm x 10 mm with 200 mm gauge length
27,8 x 0,992 = 27,6 % on 30 mm x 10 mm with 100 mm gauge length
27,8 x 1,309 = 36,4 % on 30 mm x 10 mm with 50 mm gauge length
Elongation on other proportional gauge lengths can be obtained by using the factors given in Table 1.
9 Conversion from a proportional gauge length to a non-proportional gauge
length
9.1 General
The conversion factors are variable according to the cross-sectional area of the non-proportional test
piece. Table 4 gives the multiplying factors for conversion from elongation on 56, 5 S to the equivalent
0
on fixed gauge lengths of 50 mm, 80 mm, 100 mm and 200 mm for a range of cross-sectional areas. For
conversions in the reverse direction, i.e. elongation on a fixed gauge length to the equivalent of 56, 5 S
0
, the reciprocal of the factors is used.
EXAMPLE

a) Elongation of 20 % on 56, 5 S is equivalent to 20 x 1,139 = 22,78 % on a 25 mm wide test
0
piece of 6 mm thickness with a 50 mm gauge length (see Table 4);
b) Elongation of 25 % on a 40 mm x 10 mm test piece of 200 mm gauge length is equivalent to
25 x 1/0,796 = 31,4 % on 56, 5 S (see Table 4).
0
From the examples shown, it will be seen that conversions involving other proportional gauge lengths
can be obtained by prior or subsequent use of the factors shown in Table 1.
4 © ISO 2021 – All rights reserved

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

9.2 Conversion factors from 56, 5 S to non-proportional gauge length
0
Factors shown under “non-proportional gauge lengths” give the value of
04,
 
S
0
2
 
L
 
To convert from values on a gauge length of 56, 5 S to a non-proportional gauge length, multiply by
0
the appropriate factor.
To convert from values on a non-proportional gauge length to 56, 5 S , divide by the appropriate
0
factor.
See also Figures 1 and 2.
Table 4 — Conversion factors from 56, 5 S to non-proportional gauge lengths
0
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
5 0,331 0,437 0,478 0,577
10 0,381 0,502 0,549 0,663
15 0,413 0,545 0,596 0,719
20 0,437 0,577 0,631 0,761
25 0,457 0,603 0,660 0,796
30 0,474 0,626 0,684 0,826
35 0,489 0,645 0,706 0,852
40 0,502 0,663 0,725 0,875
45 0,514 0,679 0,742 0,896
50 0,525 0,693 0,758 0,915
55 0,535 0,706 0,772 0,932
60 0,545 0,719 0,786 0,949
70 0,562 0,741 0,811 0,978
80 0,577 0,761 0,833 1,005
90 0,591 0,780 0,852 1,029
100 0,603 0,796 0,871 1,051
110 0,615 0,812 0,887 1,071
120 0,626 0,826 0,903 1,090
130 0,636 0,839 0,917 1,107
140 0,645 0,852 0,931 1,124
150 0,654 0,863 0,944 1,139
160 0,663 0,875 0,956 1,154
170 0,671 0,885 0,968 1,168
180 0,679 0,896 0,979 1, 182
190 0,686 0,905 0,990 1,195
200 0,693 0,915 1,000 1,207
210 0,700 0,924 1,010 1,219
220 0,706 0,932 1,019 1,230
230 0,713 0,941 1,028 1,241
© ISO 2021 – All rights reserved 5

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

Table 4 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
240 0,719 0,949 1,037 1,252
250 0,725 0,956 1,046 1,262
260 0,730 0,964 1,054 1,272
270 0,736 0,971 1,062 1,281
280 0,741 0,978 1,070 1,291
290 0,747 0,985 1,077 1,300
300 0,752 0,992 1,084 1,309
310 0,757 0,998 1,092 1,317
320 0,761 1,005 1,099 1,326
330 0,766 1,011 1,105 1,334
340 0,771 1,017 1,112 1,342
350 0,775 1,023 1,118 1,350
360 0,780 1,029 1,125 1,357
370 0,784 1,034 1,131 1,365
380 0,788 1,040 1,137 1,372
390 0,792 1,045 1,143 1,379
400 0,796 1,051 1,149 1,386
410 0,800 1,056 1,154 1,393
420 0,804 1,061 1,160 1,400
430 0,808 1,066 1,165 1,406
440 0,812 1,071 1,171 1,413
450 0,815 1,076 1,176 1,419
460 0,819 1,080 1,181 1,426
470 0,822 1,085 1,186 1,432
480 0,826 1,090 1,191 1,438
490 0,829 1,094 1,196 1,444
500 0,833 1,099 1,201 1,450
550 0,849 1,120 1,224 1,477
600 0,863 1,139 1,246 1,503
650 0,877 1,158 1,266 1,528
700 0,891 1,175 1,285 1,550
750 0,903 1,191 1,303 1,572
800 0,915 1,207 1,320 1,592
850 0,926 1,222 1,336 1,612
900 0,936 1,236 1,351 1,630
950 0,947 1,249 1,366 1,648
1 000 0,956 1,262 1,380 1,665
1 050 0,966 1,274 1,393 1,681
1 100 0,975 1,286 1,406 1,697
1 150 0,983 1,298 1,419 1,712
1 200 0,992 1,309 1,431 1,727
1 250 1,000 1,320 1,443 1,741
6 © ISO 2021 – All rights reserved

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

Table 4 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
1 300 1,008 1,330 1,454 1,755
1 350 1,016 1,340 1,465 1,768
1 400 1,023 1,350 1,476 1,781
1 450 1,030 1,359 1,486 1,794
1 500 1,037 1,369 1,496 1,806
1 550 1,044 1,378 1,506 1,818
1 600 1,051 1,386 1,516 1,829
1 650 1,057 1,395 1,525 1,841
1 700 1,063 1,403 1,534 1,852
1 750 1,070 1,411 1,543 1,862
1 800 1,076 1,419 1,552 1,873
1 850 1,082 1,427 1,560 1,883
1 900 1,087 1,435 1,569 1,893
1 950 1,093 1,442 1,577 1,903
2 000 1,099 1,450 1,585 1,913
2 050 1,104 1,457 1,593 1,922
2 100 1,109 1,464 1,600 1,931
2 150 1,115 1,471 1,608 1,941
2 200 1,120 1,477 1,615 1,950
2 250 1,125 1,484 1,623 1,958
2 300 1,130 1,491 1,630 1,967
2 350 1,135 1,497 1,637 1,975
2 400 1,139 1,503 1,644 1,984
2 450 1,144 1,510 1,651 1,992
2 500 1,149 1,516 1,657 2,000
2 550 1,153 1,522 1,664 2,008
2 600 1,158 1,528 1,670 2,016
2 650 1,162 1,533 1,677 2,023
2 700 1,167 1,539 1,683 2,031
2 750 1,171 1,545 1,689 2,038
2 800 1,175 1,550 1,695 2,046
2 850 1,179 1,556 1,701 2,053
2 900 1,183 1,561 1,707 2,060
2 950 1,187 1,567 1,713 2,067
3 000 1,191 1,572 1,719 2,074
© ISO 2021 – All rights reserved 7

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

9.3 Conversion factors from 4 S to non-proportional gauge length
0
Factors shown under “non-proportional gauge length” give the value of
04,
 
S
0
17, 4
 
L
 
To convert from values on a gauge length of 4 S to a non-proportional gauge length, multiply by the
0
appropriate factor.
To convert from values on a non-proportional gauge length to 4 S divide by the appropriate factor.
0
See also Figures 3 and 4.
Table 5 — Conversion factors from 4 S to non-proportional gauge length
0
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
5 0,288 0,380 0,416 0,502
10 0,331 0,437 0,478 0,577
15 0,359 0,474 0,518 0,625
20 0,380 0,502 0,549 0,662
25 0,398 0,525 0,574 0,693
30 0,413 0,544 0,595 0,718
35 0,426 0,562 0,614 0,741
40 0,437 0,577 0,631 0,761
45 0,447 0,590 0,646 0,779
50 0,457 0,603 0,659 0,796
55 0,466 0,615 0,672 0,811
60 0,474 0;625 0,684 0,825
70 0,489 0,645 0,705 0,851
80 0,502 0,662 0,724 0,874
90 0,514 0,678 0,742 0,895
100 0,525 0,693 0,757 0,914
110 0,535 0,706 0,772 0,932
120 0,544 0,718 0,786 0,948
130 0,553 0,730 0,798 0,963
140 0,562 0,741 0,810 0,978
150 0,560 0,751 0,821 0,991
160 0,577 0,761 0,832 1,004
170 0,584 0,770 0,642 1,016
180 0,590 0,779 0,852 1,028
190 0,597 0,788 0,861 1,039
200 0,603 0,796 0,870 1,050
210 0,609 0,804 0,879 1,060
220 0,615 0,811 0,887 1,070
230 0,620 0,818 0,895 1,080
240 0,625 0,825 0,902 1,089
8 © ISO 2021 – All rights reserved

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

Table 5 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
250 0,631 0,832 0,910 1,098
260 0,636 0,839 0,917 1,107
270 0,640 0,845 0,924 1,115
280 0,645 0,851 0,931 1,123
290 0,650 0,857 0,937 1,131
300 0,654 0,863 0,943 1,139
310 0,658 0,869 0,950 1,146
320 0,662 0,874 0,956 1,153
330 0,667 0,880 0,962 1,161
340 0,671 0,885 0,967 1,168
350 0,674 0,890 0,973 1,174
360 0,678 0,895 0,979 1,181
370 0,682 0,900 0,984 1,187
380 0,686 0, 905 0,989 1,194
390 0,689 0,909 0,994 1,200
400 0,693 0,914 0,999 1,206
410 0,696 0,919 1,004 1,212
420 0,699 0,923 1,009 1,218
430 0,703 0,927 1,014 1,224
440 0,706 0,932 1,019 1,229
450 0,709 0,936 l,023 1,235
460 0,712 0,940 1,028 1,240
470 0,715 0,944 1,032 1,246
480 0,718 0,948 1,036 1,251
490 0,721 0,952 1,041 1,256
500 0,724 0,956 1,045 1,261
550 0,738 0,974 1,065 1,285
600 0,751 0,991 1,084 1,308
650 0,763 1,007 1,101 1,329
700 0,775 1,022 1,118 1,349
750 0,786 1,036 1,133 1,368
800 0,796 1,050 1,148 1,385
850 0,805 1,063 1,162 1,402
900 0,815 1,075 1,175 1,418
950 0,824 1,087 1,188 1,434
1 000 0,832 1,098 1,200 1,449
1 050 0,840 1,109 1,212 1,463
1 100 0,848 1,119 1,223 1,477
1 150 0,856 1,129 1,234 1,490
1 200 0,863 1,139 1,245 1,502
1 250 0,870 1,148 1,255 1,515
1 300 0,877 1,157 1,265 1,527
© ISO 2021 – All rights reserved 9

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

Table 5 (continued)
Cross sectional
Factor for non-proportional gauge length of:
area of test piece:
2
mm 200 mm 100 mm 80 mm 50 mm
1 350 0,883 1,166 1,275 1,538
1 400 0,890 1,174 1,284 1,549
1 450 0,896 1,183 1,293 1,560
1 500 0,902 1,191 1,302 1,571
1 550 0,908 1,198 1,310 1,581
1 600 0,914 1,206 1,319 1,591
1 650 0,920 1,214 1,327 1,601
1 700 0,925 1,221 1,335 1,611
1 750 0,931 1,228 1,343 1,620
1 800 0,936 1,235 1,350 1,629
1 850 0,941 1,242 1,358 1,638
1 900 0,946 1,248 1,365 1,647
1 950 0,951 1,255 1,372 1,656
2 000 0,956 1,261 1,379 1,664
2 050 0,960 1,267 1,386 1,672
2 100 0,965 1,273 1,392 1,680
2 150 0,970 1,279 1,399 1,688
2 200 0,974 1,285 1,405 1,696
2 250 0,979 1,291 1,412 1,704
2 300 0,983 1,297 1,418 1,711
2 350 0,987 1,302 1,424 1,719
2 400 0,991 1,308 1,430 1,726
2 450 0,995 1,313 1,436 1,733
2 500 0,999 1,319 1,442 1,740
2 550 1,003 1,324 1,448 1,747
2 600 1,007 1,329 1,453 1,754
2 650 1,011 1,334 1,459 1,760
2 700 1,015 1,339 1,464 1,767
2 750 1,019 1,344 1,470 1,773
2 800 1,022 1,349 1,475 1,780
2 850 1,026 1,354 1,480 1,786
2 900 1,029 1,358 1,485 1,792
2 950 1,033 1,363 1,490 1,799
3 000 1,036 1,368 1,495 1,805
9.4 Elongation values
Tables 6 to 9 can be used for conversion to 56, 5 S , whilst Tables 14 to 17 can be used to obtain
0
elongation on fixed gauge lengths corresponding to 56, 5 S . Similarly, Tables 10 to 13 can be used for
0
conversion to 4 S and Tables 18 to 21 for elongations on fixed gauge lengths corresponding to 4 S
0 0
.
10 © ISO 2021 – All rights reserved

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oSIST prEN ISO 2566-1:2021
ISO/FDIS 2566-1:2021(E)

a
Table 6 — Elongation values on 56, 5 S corresponding to those obtained on 50 mm gauge
0
length
Actual elon-
Corresponding elongation (%) on 56, 5 S gauge length if cross-sectional area in square millimetres is:
gation (%) on
0
50 mm gauge
length
5 10 20 40 60 80 100 150 200 250 300 400 500 600 700 800 900 1 000 1 200 1 500 2 000 2 500
18 31 27 24 21 19 18 17 16 15 14 14 13 12 12 12 11 11 11 10 10 9 9
19 33 29 25 22 20 19 18 17 16 15 15 14 13 13 12 12 12 11 11 11 10 10
20 35 30 26 23 21 20 19 18 17 16 15 14 14 13 13 13 12 12 12 11 10 10
21 36 32 28 24 22 21 20 18 17 17 16 15 14 14 14 13 13 13 12 12 11 11
22 38 33 29 25 23 22 21 19 18 17 17 16 15 15 14 14 13 13 13 12 12 11
23 40 35 30 26 24 23 22 20 19 18 18 17 16 15 15 14 14 14 13 13 12 12
24 42 36 32 27 25 24 23 21 20 19 18 17 17 16 15 15 15 14 14 13 13 12
25 43 38 33 29 26 25 24 22 21 20 19 18 17 17 16 16 15 15 14 14 13 13
26 45 39 34 30 27 26 25 23 22 21 20 19 18 17 17 16 16 16 15 14 14 13
27 47 41 35 31 28 27 26 24 22 21 21 19 19 18 17 17 17 16 16 15 14 14
28 49 42 37 32 30 28 27 25 23 22 21 20 19 19 18 18 17 17 16 16 15 14
29 50 44 38 33 31 29 28 25 24 23 22 21 20 19 19 18 18 17 17 16 15 15
30 52 45 39 34 32 30 29 26 25 24 23 22 21 20 19 19 18 18 17 17 16 15
31 54 47 41 35 33 31 30 27 26 25 24 22 21 21 20 19 19 19 18 17 16 16
32 55 48 42 37 34 32 30 28 27 25 24 23 22 21 21 20 20 19 19 18 17 16
33 57 50 43 38 35 33 31 29 27 26 25 24 23 22 21 21 20 20 19 18 17 17
34 59 51 45 39 36 34 32 30 28 27 26 25 23 23 22 21 21 20 20 19 18 17
35 61 53 46 40 37 35 33 31 29 28 27 25 24 23 23 22 21 21 20 19 18 18
36
...

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