SIST EN 14607-8:2005

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Vesoljska tehnika – Mehanika - 8. del: MaterialiRaumfahrttechnik - Mechanik - Teil 8: WerkstoffeIngénierie spatiale - Mécanique - Partie 8: MatériauxSpace engineering - Mechanical - Part 8: Materials49.140Vesoljski sistemi in operacijeSpace systems and operationsICS:Ta slovenski standard je istoveten z:EN 14607-8:2004SIST EN 14607-8:2005en01-januar-2005SIST EN 14607-8:2005SLOVENSKI
STANDARD



SIST EN 14607-8:2005



EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 14607-8August 2004ICS 49.140English versionSpace engineering - Mechanical - Part 8: MaterialsIngénierie spatiale - Mécanique - Partie 8: MatériauxRaumfahrttechnik - Mechanik - Teil 8: WerkstoffeThis European Standard was approved by CEN on 27 June 2003.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2004 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14607-8:2004: ESIST EN 14607-8:2005



EN 14607-8:2004 (E) 2 Contents page Foreword.4 1 Scope.5 2 Normative references.5 3 Terms and definitions and abbreviated terms.5 3.1 Terms and definitions.5 3.2 Abbreviated terms.6 4 Requirements.7 4.1 General.7 4.1.1 Overview.7 4.1.2 Applicability.7 4.1.3 Controlling documentation.7 4.2 Mission.7 4.3 Functionality.7 4.3.1 Strength.7 4.3.2 Elastic modulus.7 4.3.3 Fatigue.8 4.3.4 Fracture toughness.8 4.3.5 Creep.8 4.3.6 Micro-yielding.8 4.3.7 Coefficient of thermal expansion and coefficient of moisture expansion.8 4.3.8 Stress corrosion.9 4.3.9 Corrosion fatigue.9 4.3.10 Hydrogen embrittlement.9 4.3.11 Mechanical contact surface effects.10 4.4 Mission constraints.10 4.4.1 General.10 4.4.2 Temperature.10 4.4.3 Thermal cycling.10 4.4.4 Vacuum (outgassing).11 4.4.5 Manned environment.11 4.4.6 Offgassing, toxicity and odour.11 4.4.7 Bacterial and fungus growth.11 4.4.8 Flammability.11 4.4.9 Astronaut spacesuits.12 4.4.10 Radiation.12 4.4.11 Electrical charge and discharge.12 4.4.12 Lightning strike.13 4.4.13 Chemical (corrosion).13 4.4.14 Fluid compatibility.13 4.4.15 Galvanic compatibility.13 4.4.16 Atomic oxygen.13 4.4.17 Micrometeoroids and debris.14 4.4.18 Moisture absorption and desorption.14 4.5 Interfaces.14 4.5.1 General.14 4.5.2 Passivation layers.14 4.5.3 Anodizing.14 4.5.4 Chemical conversion.15 4.5.5 Metallic coatings (overlay and diffusion).15 4.5.6 Hard coatings.15 4.5.7 High temperature oxidation protective coatings.16 SIST EN 14607-8:2005



EN 14607-8:2004 (E)
3 4.5.8 Thermal barriers.16 4.5.9 Moisture barriers.16 4.5.10 Diffusion barriers.16 4.5.11 Coatings on CFRP.16 4.6 Joining.17 4.6.1 General.17 4.6.2 Mechanical fastening.17 4.6.3 Adhesive bonding.17 4.6.4 Fusion.18 4.7 Design.19 4.7.1 General.19 4.7.2 Material design allowables.19 4.7.3 Metal design allowables.19 4.7.4 Composite design allowables.20 4.7.5 Composite sandwich constructions.20 4.7.6 Aluminium.21 4.7.7 Steel.21 4.7.8 Titanium.22 4.7.9 Magnesium alloys.22 4.7.10 Beryllium and beryllium alloys.22 4.7.11 Mercury.22 4.7.12 Refractory alloys.22 4.7.13 Superalloys.23 4.7.14 Other metals.23 4.7.15 Castings.23 4.7.16 Forgings.23 4.7.17 Glass and ceramics.23 4.7.18 Ceramic Matrix Composites — CMC (including carbon-carbon).23 4.7.19 Polymers (thermosets and thermoplastics).23 4.7.20 Rubbers (excluding adhesive rubbers).24 4.7.21 Lubricants.24 4.7.22 Thermal control insulants (including ablative materials).25 4.7.23 Optical materials.25 4.8 Verification.25 4.8.1 General.25 4.8.2 Metallic materials.25 4.8.3 Composite materials — laminates.26 4.8.4 Mechanical and physical test methods.26 4.8.5 Test methods on metals.26 4.8.6 Test methods on composites.27 4.8.7 Non-destructive inspection (NDI).28 4.8.8 Proof testing.29 4.9 Production and manufacture.29 4.9.1 General.29 4.9.2 Procurement.29 4.9.3 Manufacturer.29 4.9.4 Supplier.29 4.10 In-service.29 4.10.1 General.29 4.10.2 Maintenance.30 4.10.3 Inspection.30 4.10.4 Repair.30 4.11 Data exchange.30 4.12 Product assurance.31 4.13 Deliverables.32 Bibliography.33
Tables Table 1 —Document requirements for materials.32 SIST EN 14607-8:2005



EN 14607-8:2004 (E)
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Foreword This document (EN 14607-8:2004) has been prepared by CMC. 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 February 2005, and conflicting national standards shall be withdrawn at the latest by February 2005. It is based on a previous version1)
originally prepared by the ECSS Mechanical Engineering Standard Working Group, reviewed by the ECSS Technical Panel and approved by the ECSS Steering Board. The European Cooperation for Space Standardization (ECSS) is a cooperative effort of the European Space Agency, National Space Agencies and European industry associations for the purpose of developing and maintaining common standards. This document is one of the series of space standards intended to be applied together for the management, engineering and product assurance in space projects and applications. Requirements in this document are defined in terms of what shall be accomplished, rather than in terms of how to organize and perform the necessary work. This allows existing organizational structures and methods to be applied where they are effective, and for the structures and methods to evolve as necessary without rewriting the standards. EN 14607 Space engineering - Mechanical is published in 8 Parts: • Part 1: Thermal control • Part 2: Structural • Part 3: Mechanisms • Part 4: ECLS • Part 5: Propulsion • Part 5.1: Liquid and electric propulsion for spacecraft • Part 5.2: Solid propulsion for spacecraft, solid and liquid propulsion for launchers • Part 6: Pyrotechnics • Part 7: Mechanical parts • Part 8: Materials According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
1) ECSS-E-30 Part 8A. SIST EN 14607-8:2005



EN 14607-8:2004 (E) 5 1 Scope EN 14607 Part 8 of Space engineering - Mechanical defines the mechanical engineering requirements for materials. This document also encompasses the effects of the natural and induced environments to which materials used for space applications can be subjected. This document defines requirements for the establishment of the required mechanical and physical properties of the materials including the effects of the environmental conditions, material selection, procurement, production and verification. Verification includes destructive and non-destructive test methods. Material procurement and control is closely related to required quality assurance procedures and detailed references to EN 13291-3 are made. When viewed from the perspective of a specific project context, the requirements defined in this document should be tailored to match the genuine requirements of a particular profile and circumstances of a project. NOTE Tailoring is a process by which individual requirements of specifications, standards and related documents are evaluated, and made applicable to a specific project by selection, and in some exceptional cases, modification of existing or addition of new requirements. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 13291-3, Space product assurance — General requirements — Part 3: Materials, mechanical parts and processes EN 13701:2001, Space systems — Glossary of terms EN 14607-2, Space engineering — Mechanical — Part 2: Structural References to sources of approved lists, procedures and processes can be found in the bibliography. 3 Terms and definitions and abbreviated terms 3.1 Terms and definitions For the purposes of this document, the terms and definitions given in EN 13701:2001 and the following apply. 3.1.1 A-basis design allowable value which at least 99 % of the population of values is expected to fall with a confidence of 95 % 3.1.2 B-basis design allowable value which at least 90 % of the population of values is expected to fall with a confidence of 95 % 3.1.3 composite sandwich construction panels composed of a lightweight core material, such as honeycomb, foamed plastic, and so forth, to which two relatively thin, dense, high-strength or high stiffness faces or skins are adhered SIST EN 14607-8:2005



EN 14607-8:2004 (E) 6 3.1.4 corrosion
reaction of the engineering material with its environment with a consequent deterioration in properties of the material 3.1.5 Elastic modulus the ratio between uniaxial stress and the strain 3.1.6 material design allowable material property that has been determined from test data on a probability basis and has been chosen to assure a high degree of confidence in the integrity of the completed structure 3.1.7 micro-yield applied force to produce a residual strain of 1 ×10-6 mm/m along the tensile or compression loading direction 3.1.8 polymer high molecular weight organic compound, natural or synthetic, with a structure that can be represented by a repeated small unit, the mer EXAMPLE Polyethylene, rubber, and cellulose. 3.2 Abbreviated terms The following abbreviated terms are defined and used within this document. Abbreviation Meaning ASTM American Society for Testing Materials CFRP carbon fibre reinforced plastic CMC ceramic matrix composites CME coefficient of moisture expansion CTE coefficient of thermal expansion DRD document requirements definition EB electron beam Kic plane strain critical stress intensity factor Kiscc plane strain critical stress intensity factor for a specific environment LEO low Earth orbit MIG metal inert gas MMC metal matrix composite MoS2 molybdenum disulphide NDE non-destructive evaluation NDI non-destructive inspection SIST EN 14607-8:2005



EN 14607-8:2004 (E) 7 NDT non-destructive test PTFE polytetrafluoroethylene RTM resin transfer moulding SCC stress corrosion cracking STS space transportation system TIG tungsten inert gas UD uni-directional UV ultra violet 4 Requirements 4.1 General 4.1.1 Overview This group of requirements covers the interaction of materials engineering requirements with project management, product assurance, and related requirements. 4.1.2 Applicability This document applies to all materials used in all space and space related products. For certain projects, it can be necessary to include further (normative) standards in addition to those referenced within this document. 4.1.3 Controlling documentation a) All materials and processes shall be defined by standards and specifications. b) Suppliers shall select EN and ECSS Standards, supplemented by agency or company standards. 4.2 Mission Mission requirements are covered in this document. 4.3 Functionality 4.3.1 Strength a) Spacecraft design shall ensure the survival of the structure under the worst feasible combination of mechanical and thermal loads for the complete lifetime of the spacecraft. b) A strength analysis shall be performed and demonstrate a positive margin of safety and include, if applicable, yield load analysis, ultimate load analysis and buckling load analysis (see EN 14607-2). NOTE The strength of a material is highly dependant on the direction as well as on the sign of the applied load, e.g. axial tensile, and transverse compressive. 4.3.2 Elastic modulus For composites the required elastic modulus shall be verified. SIST EN 14607-8:2005



EN 14607-8:2004 (E) 8 NOTE The elastic modulus for metals and alloys is weakly dependant on heat-treatment and orientation. However, for fibre reinforced materials, the elastic modulus depends on the fibre orientation. 4.3.3 Fatigue For all components subject to alternating stresses, it shall be demonstrated that the degradation of material properties over the complete mission conforms to the specification.
NOTE Fatigue fracture can form in components which are subjected to alternating stresses. These stresses can exist far below the allowed static strength of the material. 4.3.4 Fracture toughness a) For homogeneous materials the Kic or Kiscc shall be measured according to approved procedures. b) Metallic materials intended for use in corrosive surface environments shall be tested for fracture toughness under representative conditions. NOTE The fracture toughness is a measure of the damage tolerance of a material containing initial flaws or cracks. The fracture toughness in metallic materials is described by the plain strain value of the critical stress intensity factor. The fracture toughness depends on the environment. 4.3.5 Creep When creep is expected to occur, testing under representative service conditions shall be performed. NOTE Creep is a time-dependant deformation of a material under an applied load. It usually occurs at elevated temperature, although some materials creep at room temperature. If permitted to continue indefinitely, creep terminates in rupture. Extrapolations from simple to complex stress-temperature-time conditions are difficult. 4.3.6 Micro-yielding a) Where dimensional stability requirements shall be met, micro-yielding shall be assessed. b) When micro-yielding is expected to occur, testing and analysis in relation with the mechanical loading during the life cycle of the hardware shall be performed. NOTE
1 Some materials can exhibit residual strain after mechanical loading. NOTE
2 In general the most severe mechanical loading occurs during launch. 4.3.7 Coefficient of thermal expansion and coefficient of moisture expansion a) Thermal coefficient mismatch between structural members shall be minimized such that stresses generated in the specified temperature range for the item are acceptable. b) The coefficient of thermal expansion (CTE) of composite materials intended for high stability structural applications shall be systematically determined by means of dry test coupons under dry test conditions. c) For hygroscopic materials intended for high stability structural applications, the coefficient of moisture expansion (CME) shall be systematically determined. d) A sensitivity analysis which takes in consideration the inaccuracies inherent in the manufacturing process shall be performed for all composite materials. NOTE The difference in thermal or moisture expansion between members of a construction or between the constituents of a composite or a coated material can induce large stresses or strains and can finally lead to failures. SIST EN 14607-8:2005



EN 14607-8:2004 (E) 9 4.3.8 Stress corrosion a) Metallic structural products shall be selected from preferred lists. b) The metallic components proposed for use in most spacecraft shall be screened to prevent failures resulting from stress corrosion cracking (SCC). NOTE Stress corrosion cracking (SCC), defined as the combined action of a sustained tensile stress and corrosion, can cause the premature failure of metals. c) Only those products found to possess a high resistance to stress corrosion cracking shall have unrestricted use in structural applications. d) Materials selected for structural applications shall possess a high resistance to stress corrosion cracking, if they are • exposed to a long-term storage on ground (terrestrial), • flown on the Space Transportation System (STS),
• classified as fracture critical items, or • parts associated with the fabrication of launch vehicles. e) The technical criteria, for the selection of materials, of EN 13291-3 shall apply. 4.3.9 Corrosion fatigue For all materials in contact with chemicals and experiencing an alternating loading it shall be demonstrated that the degradation of properties over the complete mission is acceptable. NOTE Corrosion fatigue indicates crack f
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