1、ASD STANDARD NORME ASD ASD NORM prEN 2950 Edition P 1 February 2007 PUBLISHED BY THE AEROSPACE AND DEFENCE INDUSTRIES ASSOCIATION OF EUROPE - STANDARDIZATIONAvenue de Tervuren, 270 - B-1150 Brussels - Tel. + 32 2 775 8126 - Fax. + 32 2 763 3565 - www.asd-stan.orgICS: Descriptors: ENGLISH VERSION Aer
2、ospace series Test method Wrought heat resisting alloys Semi-finished products and parts Conditions for macrographic and micrographic examination Atlas of structures and defects Srie arospatiale Mthode dessais Demi-produits et pices corroys en alliage rsistant chaud Conditions dexamens macrographiqu
3、e et micrographique Atlas de structures et de dfauts Luft- und Raumfahrt Prfverfahren Umgeformte Erzeugnisse aus hochwarmfesten Legierungen Prfbedingungen fr makrographische und mikrographische Untersuchung Gefge- und Fehleratlas This “Aerospace Series“ Prestandard has been drawn up under the respon
4、sibility of ASD-STAN (The AeroSpace and Defence Industries Association of Europe - Standardization). It is published for the needs of the European Aerospace Industry. It has been technically approved by the experts of the concerned Domain following member comments. Subsequent to the publication of t
5、his Prestandard, the technical content shall not be changed to an extent that interchangeability is affected, physically or functionally, without re-identification of the standard. After examination and review by users and formal agreement of ASD-STAN, it will be submitted as a draft European Standa
6、rd (prEN) to CEN (European Committee for Standardization) for formal vote and transformation to full European Standard (EN). The CEN national members have then to implement the EN at national level by giving the EN the status of a national standard and by withdrawing any national standards conflicti
7、ng with the EN. Edition approved for publication 28 February 2007 Comments should be sent within six months after the date of publication to ASD-STAN Metallic Material Domain Copyright 2007 by ASD-STAN prEN 2950:20072 Contents Page Foreword2 1 Scope 3 2 Normative references 3 3 Terms and definitions
8、 .3 4 Macrographic examination .4 5 Micrographic examination 6 6 Reporting of results.7 Annex A (normative) Atlas of macrographic references 8 Annex B (normative) Atlas of micrographic references .31 Foreword This standard was reviewed by the Domain Technical Coordinator of ASD-STANs Metallic Materi
9、al Domain. After inquiries and votes carried out in accordance with the rules of ASD-STAN defined in ASD-STANs General Process Manual, this standard has received approval for Publication. prEN 2950:20073 1 Scope The present document defines the conditions for the macrographic and micrographic examin
10、ation of heat resisting alloy semi-finished and parts. It includes an atlas of commonly encountered and structural defects. The present document shall be applied in conjunction with the material standards specifying the criteria of acceptance. The present document is not intented to apply to cast or
11、 powder metallurgy products. 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) applie
12、s. EN 2078, Aerospace series Metallic materials Manufacturing schedule, inspection schedule, inspection and test report Definition, general principles, preparation and approval. 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 tree rings one o
13、r more concentric or non-concentric rings evidenced by a difference in texture associated with minor composition gradients due to ingot solidification 3.2 dendritic aspect coarse structure having a fir-tree like appearance initiated during the solidification of the ingot 3.3 grain flow fibre like li
14、nes which are caused by orientation of the constituents of the metal during deformation 3.4 recrystallisation formation of a new grain structure from that existing previously 3.5 freckles a type of segregation consisting of circular or near-circular dark etching areas, generally enriched with carbid
15、es and hardening elements 3.6 white spots a type of segregation consisting of bright white areas having bulk or fibrous configuration, generally depleted in carbides and hardening elements 3.7 stringer predominantly straight linear formation which is 2 particles in width prEN 2950:20074 3.8 cluster
16、predominantly straight elongated formation which is mainly 2 particles in width 3.9 chain linear formation whose particle distribution does not lie predominantly in a straight line 3.10 random distribution of particles with no particular orientation 4 Macrographic examination 4.1 General Macrographi
17、c examination shall be carried out in accordance with this standard and by reference to Annex A (normative) to verify that the requirements of the relevant material standard, technical specification or order have been met. 4.2 Product surface examination 4.2.1 General Examination shall be performed
18、on the entire surface of the product in the delivery heat treatment condition unless otherwise agreed between the manufacturer and the purchaser. Handling zones which may cause imperfect etching shall be defined and agreed between the manufacturer and the purchaser, and shall not be taken into accou
19、nt in the evaluation. 4.2.2 Surface preparation Preparation shall not alter, contaminate or cold work the surface structure. The product shall be cleaned and degreased to ensure uniform etching. 4.2.3 Macroetching The etching method to be used shall be agreed between the manufacturer and purchaser.
20、A list of typical etching reagents and conditions are given in Table 1. All structural characteristics, particularly the segregation resulting from solidification of the ingot shall be revealed. After etching, the surfaces shall be cleaned in a way which does not affect the quality of the contrast a
21、nd shall be protected from deterioration and contamination until inspection is carried out. 4.2.4 Examination Examination shall be carried out under a minimum light intensity of 250 Lux. Examination shall normally be performed without magnification but when necessary may be supplemented by the use o
22、f a magnification up to a maximum of 12. In case of doubt or when the structural features are unusual, a micrographic examination of the affected area shall be made in accordance with clause 5. prEN 2950:20075 4.3 Cut-up examination 4.3.1 General Unless otherwise agreed between the manufacturer and
23、the purchaser, examination shall be performed on a plane section of the product in the delivery heat treatment condition. The location and orientation of the plane section shall be as required by the relevant technical specification or order. The cutting method shall not cause damage to the structur
24、e. Slices shall be of sufficient thickness to allow further examination perpendicular to this plane section if required. 4.3.2 Surface preparation The surface to be examined shall be prepared in such a way that any contamination and mechanical alteration of the surface are avoided or eliminated. The
25、 resulting surface shall be cleaned and degreased to ensure uniform etching. 4.3.3 Macroetching Wherever possible, electro-chemical techniques shall be used. The etching method to be used, shall be carried out by a technical agreed between manufacturer and purchaser. A list of typical etching reagen
26、ts and conditions is given in Table 1. Etching shall reveal all structure characteristics, particularly segregation resulting from the ingot solidification. After etching the surface shall be cleaned in a way which does not affect the quality of the contrast and shall be protected from deterioration
27、 and contamination until inspection is carried out. Table 1 Etchant Alloy type Name Composition vol. % Conditions Fe, Ni base Hydrochloric etch HCl . 50 H2O 50 Electrolytic (40 A/dm2 l 100 A/dm2) Ambient temperature Fe, Ni base with Nb Ferric chloride FeCl3 .49 HCl . 4 H2O 47 Chemical 40 C 120 C Fe,
28、 Ni, Co base Sulphuric etch H2SO4 95 H2O 5 Electrolytic 25 A/dm2Ambient temperature 4.3.4 Examination Macrographic examination shall be carried out in accordance with 4.2.4. prEN 2950:2007 6 5 Micrographic examination 5.1 General Micrographic examination shall be carried out in accordance with this
29、standard and by reference to Annex B (normative) and to verify the requirements of the relevant material standard and/or order have been met. 5.2 Product surface examination 5.2.1 General Examination shall be carried out to investigate anomalies observed during macrographic examination (see 4.2.4) o
30、r when required by the material standard. 5.2.2 Surface preparation Material shall be removed from the surface to be examined until it is polished to a mirror finish and is free from cold working, contamination and the effects of prior surface preparation. 5.2.3 Microetching Micro examination may be
31、 required in either or both polished and etched conditions. When etching is required, the method to be used shall be agreed between manufacturer and purchaser. A list of typical etching reagents and conditions is given in Table 2. After etching, the surfaces shall be cleaned in a way which does not
32、affect the quality of the contrast, and shall be protected from deterioration and contamination until examination is carried out. Table 2 Etchant Alloy type Name Composition Conditions Co base Nital 2 % HNO3 10 % ethyl alcohol Electrolytic Ambient temperature Fe, Ni base low Al, Ti content Frys reag
33、ent CuCl2. 20 gHCl . 200 ml H2O 100 ml Chemical Ambient temperature Fe, Ni, Co base Murakamis reagent KOH 10 g K3Fe(CN)4. 8 g H2O 100 ml Chemical 60 C 90 C Ni base high Al, Ti content Glyceregia HCl . 20 ml HNO3. 10 ml Glycerol . 35 ml Electrolytic Ambient temperature Ni base High Cr, Al, Ti content
34、 HF/Glycerol HF . 5 ml Glycerol . 10 ml H2O 85 ml Electrolytic Ambient temperature 5.2.4 Examination Examination shall be carried out directly on the prepared surface or by using a replica, under an optical microscope with a minimum magnification of 50. prEN 2950:2007 7 Wherever possible examination
35、 shall be made at the same magnification as the reference photomicrograph. In all cases, the magnification used shall permit resolution of the structural characteristics sought. 5.3 Cut-up examination 5.3.1 General Examination shall be carried out on a plane section of the product in order to invest
36、igate anomalies observed during macrographic examination (see 4.3.4) or when required by the material standard, technical specification or order. In case of such a requirement, this examination shall be carried out in the heat treatment condition required by the relevant material standard. 5.3.2 Sam
37、pling The location and orientation of samples shall be as required by the relevant material standard or order or as determined by the presence of macro anomalies. The sampling method shall not cause damage to the structure. 5.3.3 Surface preparation The surface preparation shall be carried out in ac
38、cordance with 5.2.2. 5.3.4 Microetching Microetching shall be carried out in accordance with 5.2.3. 5.3.5 Examination Examination shall be carried out in accordance with 5.2.4. 6 Reporting of results The results of macro or micro examination shall be recorded in the inspection and test report in acc
39、ordance with EN 2078. Each photograph of the structure shall be identified with the location, orientation, etch method and magnification. prEN 2950:20078 Annex A (normative) Atlas of macrographic references A.1 Tree rings A.1.1 Concentric tree rings See Figure A.1 (A to E). A B prEN 2950:20079 C D p
40、rEN 2950:200710 E Figure A.1 prEN 2950:200711 A.1.2 Non-concentric tree ring See Figure A.2 (A to F). A B prEN 2950:200712 C D prEN 2950:200713 E F Figure A.2 prEN 2950:200714 A.2 Dendritic aspect See Figure A.3 (A to E). A B prEN 2950:200715 C D prEN 2950:200716 E Figure A.3 prEN 2950:200717 A.3 Gr
41、ain flow A.3.1 Regular See Figure A.4. Figure A.4 A.3.2 Irregular See Figure A.5. Figure A.5 prEN 2950:200718 A.4 Macro-recrystalisation A.4.1 Central coarsening See Figure A.6. Figure A.6 A.4.2 Central and outer See Figure A.7. Figure A.7 prEN 2950:200719 A.4.3 Central and ring See Figure A.8. Figu
42、re A.8 A.4.4 Random See Figure A.9. Figure A.9 prEN 2950:200720 A.4.5 Square shape recrystalisation See Figure A.10 (A to H). Figure A.10 A.4.6 Outer critical grain growth See Figure A.11. Figure A.11 prEN 2950:200721 A.5 Freckles See Figure A.12 (A to G), Figure A.13 and Figure A.14. ABCDprEN 2950:
43、200722 Figure A.12 FGEprEN 2950:200723 Figure A.13 prEN 2950:200724 Figure A.14 prEN 2950:200725 A.6 White spots A.6.1 Density See Figure A.15 (A to E). A B prEN 2950:200726 Figure A.15 CDEprEN 2950:200727 A.6.2 Illustration A.6.2.1 Bulk See Figure A.16. Figure A.16 A.6.2.2 Fibrous See Figure A.17.
44、Figure A.17 1 1/2prEN 2950:200728 A.6.2.3 Ghost See Figure A.18. Figure A.18 A.7 Cracks, forging laps A.7.1 Cracks See Figure A.19 (A and B). A B Figure A.19 prEN 2950:200729 A.7.2 Forging laps See Figure A.20. Figure A.20 A.8 Non-metallic inclusion See Figure A.21. Figure A.21 100R1 0,5prEN 2950:200730 A.9 Metallic inclusions See Figure A.22. Figure A.22
