1、_ 6$(7HFKQLFDO6WDQGDUGV%RDUG5XOHVSURYLGHWKDW7KLVUHSRUWLVSXEOLVKH GE6$(WRDGYDQFHWKHVWDWHRIWHFKQLFDODQGHQJL neering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular uVHLQFOXGLQJDQSDWHQWLQIULQJHPHQWDULVLQJWKHUHIURPLVWKHVROHUHVSRQVLELOLWRIW
2、KHX VHU SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions. Copyright 2016 SAE International All rights reserved. No part of this publication may be reproduced, stored in
3、 a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-4970 (outside USA) Fax: 724-776-0790 Email
4、: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/standards.sae.org/AMS2670J AEROSPACE MATERIAL SPECIFICATION AMS2670 REV. J Issued 1947-12 Revised 2006-06 Reaffirmed 2016-12 Superseding AMS2670H Brazin
5、g, Copper RATIONALE AMS2670J has been reaffirmed to comply with the SAE five-year review policy. 1. SCOPE 1.1 Purpose This specification covers the requirements for producing brazed joints using copper as the brazing filler metal. 1.2 Application This process has been used typically for joining carb
6、on steels, low-alloy steels, and corrosion and heat resistant steels and alloys. It is not recommended for use on parts which will operate in service over 1000 F (538 C) or requiring high strength joints for service over 700 F (371 C), but usage is not limited to such applications. 1.3 Safety - Haza
7、rdous MaterIals While the materials, methods, applications, and processes described or referenced in this specification does not address the hazards which may be involved in such use. It is the sole responsibility of the user to ensure familiarity with the safe and proper use of any hazardous materi
8、als and to take necessary precautionary measures to ensure the health and safety of all personnel involved. 2. APPLICABLE DOCUMENTS The issue of the following documents in effect on the date of the purchase order forms a part of this specification to the extent specified herein. The supplier may wor
9、k to a subsequent revision of a document unless a specific document issue is specified. When the referenced document has been canceled and no superseding document has been specified, the last published issue of that document shall apply. 2.1 SAE Publications Available from SAE International, 400 Com
10、monwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. AMS 2418 Plating, Copper AMS 2424 Plating, Nickel, Low-Stressed Deposit AMS 2635 Radiographic Inspection AMS 3430 Brazing Filler Metal, Paste, Copper, Water Thinning AMS
11、4500 Copper Sheet, Strip and Plate, Soft Annealed AMS 4501 Copper Sheet, Strip and Plate, Oxygen Free, Light Cold Rolled AMS 4701 Copper Wire, Oxygen Free, 99.95 (Cu + Ag), Annealed AMS 4740 Copper Powder, 99.0 Cu, Minimum, As Fabricated 2.2 ASTM Publications Available from ASTM International, 100 B
12、arr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM B 660 Packaging/Packing of Aluminum and Magnesium Products ASTM E 1742 Radiographic Examination 3. TECHNICAL REQUIREMENTS 3.1 Materials 3.1.1 Filler metal shall be copper conforming to AMS 4500,
13、AMS 4501, AMS 4701, or AMS 4740, or copper paste conforming to AMS 3430. Alternatively, copper plating conforming to AMS 2418 not extending beyond the intended joint and fillet area may be used. 3.1.2 Flux Paste or liquid flux shall not be used unless permitted by purchaser. 3.2 Equipment Furnaces,
14、with suitable protective atmospheres, as defined in 3.3, shall be used for brazing. Alternatively, induction heating using a protective atmosphere in a jacket surrounding the work may be used. Where brazing is concurrent with heat treatment, the pyrometry requirements of the applicable heat treatmen
15、t specification shall be applicable. 3.3 Atmospheres Brazing shall be conducted in any of the following atmospheres: 3.3.1 Argon of not less than 99.99% purity and dew point not higher than -35 F (-37 C). 3.3.2 Hydrogen of not less than 99.99% purity and dew point not higher than -25 F (-32 C). Hydr
16、ogen derived from dissociated ammonia is not permitted. 3.3.3 Any mixture of hydrogen and argon, each conforming to 3.3.1 or 3.3.2, may be used. 3.3.4 Partial vacuum not exceeding an absolute pressure of 0.020 Torr (2.7 Pa) argon conforming to 3.3.1 or hydrogen conforming to 3.3.2 may be used to sup
17、press copper evaporation. 3.3.5 Atmosphere other than those listed in 3.3.1 to 3.3.4 may be used when authorized in writing by purchaser, provided such atmospheres will not cause scaling, carburization or decarburization, nitriding, or other undesirable surface effects, and all other technical requi
18、rements of this specification are met. 3.4 Preparation 3.4.1 Surface Condition The surfaces to be joined shall be clean prior to assembly. SAE INTERNATIONAL AMS2670J 2 OF 63.4.1.1 Plating For base metals containing a specified minimum or range of aluminum and/or titanium, surfaces to be brazed and a
19、djacent areas not exceeding 1/4 inch (6.4 mm) from the joint may be plated 0.0001 to 0.0006 inch (2.5 to 15 m) thick, using nickel plating in accordance with AMS 2424. As an alternative copper plating in accordance with AMS 2418 may be used; when used, copper plate thickness shall be not less than 0
20、.0001 inch (2.5 m) but may be as thick as necessary to provide filler metal.3.4.2 Fluxing When use of a flux is permitted by purchaser, flux shall be applied to the joint areas of parts.3.4.3 Assembly 3.4.3.1 Clearances Tight or interference fit is preferred. Where not specified, joint gap shall be
21、within the range of 0.002 inch (0.05 mm) clearance to 0.002 inch (0.05 mm) interference. For joints where copper plating is used as the source for filler metal, interference fits are required. 3.4.3.2 Fixturing Self-fixturing is desirable. Parts shall be supported so that they will be in proper alig
22、nment after brazing. No form of welding on tube assemblies is permitted unless authorized in writing by purchaser. 3.4.3.3 Filler Metal Preplacement Electroplated copper may be on one or both surfaces to be joined. For all other cases, filler metal shall be preplaced at only one end of the joint exc
23、ept as permitted in 3.4.3.3.1. For blind joints, the filler metal shall be placed at the blind end of the joint and electroplated filler metal shall not be used. 3.4.3.3.1 Shims or filler metal may be preplaced within the joint when authorized by purchaser. 3.5 Procedure 3.5.1 Joining Parts shall be
24、 heated in equipment defined in 3.2, using an atmosphere defined in 3.3, to a selected temperature within the range 2000 to 2100 F (1093 to 1149 C), held at the selected temperature within 25 F (14 C) until the copper melts and flows to fill the joint. 3.5.2 Cooling After brazing, assemblies shall b
25、e cooled so as to prevent cracks and minimize internal stress, distortion, scaling, and decarburization. Cooling from the brazing temperature to below the scaling temperature shall be done in one of the atmospheres described in 3.3. If hardening is done in conjunction with brazing, cooling procedure
26、s may be revised accordingly.3.6 Post Treatment 3.6.1 Flux Removal After brazing and cooling, the residues of flux, if used, shall be completely removed from the parts by a method not injurious to the specified surface finish. SAE INTERNATIONAL AMS2670J 3 OF 63.6.2 Heat Treatment For martensitic ste
27、els, where heat treatment is required and the normal heat treatment temperature for the base metal is less than 1980 F (1082 C), such heat treatment shall be conducted in a separate operation after cooling from the brazing temperature. 3.7 Rebrazing Parts may be rebrazed a maximum of two times using
28、 the original brazing process and time and temperature cycle. Braze filler metal may be added at the original location of filler metal preplacement, or if the joint is subjected to nondestructiveexamination such as radiography, ultrasonic examination or proof test, to any area of the joint, provided
29、 there is evidence of satisfactory wetting and flow at that area of the joint. 3.8 Properties Brazed parts shall conform to the following requirements: 3.8.1 Appearance 3.8.1.1 Examination of all visible joint edges shall show a complete line or fillet of copper between component parts at both ends
30、of the joint. 3.8.1.2 Surfaces of parts shall be free from excessive filler metal that interferes with form, fit, or function. 3.8.1.3 The presence of unflowed filler metal is not acceptable. 3.8.2 Coverage The area joined by copper shall be not less than 80% of the area of the mating portions of th
31、e assembly. Method for determination shall be as acceptable to purchaser. 3.8.3 Proof Test When specified, any part from a lot shall pass a proof test. Standards for acceptance and method of test shall be as agreed upon by purchaser and processor. 3.9 Quality Brazed joints, as received by purchaser,
32、 shall be sound, clean, and free from foreign materials and from imperfections detrimental to performance of the brazed joints. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The processor of brazed assemblies shall supply all samples for processors tests and shall be responsible
33、for the performance of all required tests. When parts are required to be tested, the parts shall be supplied by the purchaser. Purchaser reserves the right to sample and to perform any confirmatory testing deemed necessary to ensure that processing conforms to specified requirements. 4.2 Classificat
34、ion of Tests 4.2.1 Acceptance Tests All technical requirements are acceptance tests and shall be performed on each lot. SAE INTERNATIONAL AMS2670J 4 OF 64.2.2 Preproduction Tests All technical requirements are preproduction tests and shall be performed prior to or on the initial shipment of brazed p
35、arts to a purchaser and when purchaser deems confirmatory testing to be required. 4.3 Sampling and testing shall be not less than the following; a lot shall be all assemblies of the same part number brazed in the same equipment without breakdown of setup and presented for processors inspection at on
36、e time. 4.3.1 Visual Each assembly. 4.3.2 Coverage 4.3.2.1 When coverage is determined destructively by tear test or metallographic examination, test frequency shall be not less than one part per lot or one part per 100 parts brazed, whichever is more frequent. 4.3.2.2 When coverage is determined no
37、n-destructively, as for example, by radiography in accordance with AMS 2635 or ASTM E 1742 or ultrasonic inspection of the joints in accordance with a procedure specified by purchaser; test frequency shall be agreed upon by purchaser and processor. Failure of any part shall be cause for 100% inspect
38、ion of the lot. 4.3.2.3 Examination for braze internal coverage may be waived when parts are proof tested in accordance with 3.8.3 and 4.3.3. 4.3.3 Proof Test When a proof test is required, any part shall pass a proof test. Standards for acceptance and method of test shall be as agreed upon by purch
39、aser and processor. Failure of any part to pass proof test requirements shall be cause for 100% testing of the lot. 4.3.4 For preproduction testing, at least one joint shall be destructively examined for braze coverage and for evidence of surface contamination due to carburization, decarburizing, ni
40、triding, or other deleterious effects. 4.4 Approval 4.4.1 The process and control procedures, or a preproduction sample part, or both, whichever is specified by purchaser, shall be approved by purchaser before production parts are supplied. 4.4.2 If the processor makes a significant change to any ma
41、terial, process, or control factor from that which was used for approval, all preproduction tests shall be performed and results submitted to purchaser for process reapproval unless the change is approved by the cognizant engineering organization. A significant change is one which, in the judgment o
42、f the cognizant engineering organization, could affect the properties or performance of the parts. 4.4.3 Control factors shall include but not be limited to the following:Surface preparation, including use of plating Complete description of flux, if used Brazing filler metal preplacement, location,
43、quantity, and form Method for fixturing, including types and locations of tack welds if used Type of heating equipment AtmosphereOrientation of parts in the furnace Braze temperature and time at temperature Heating and cooling rates Method for flux removal, if used Methods for post braze examination
44、 of joints Number of rebraze cycles SAE INTERNATIONAL AMS2670J 5 OF 64.5 Reports The processor of brazed parts shall furnish with each shipment a report stating that the parts have been brazed and tested in accordance with specified requirements and that they conform to specified requirements. This
45、report shall include braze filler metal specification, atmosphere, purchase order number, lot number, AMS 2670J, part number, quantity.5. PREPARATION FOR DELIVERY 5.1 Brazed assemblies shall be handled and packaged to ensure that the required physical characteristics and properties of the assemblies
46、 will be preserved. 5.2 Packages of brazed parts shall be prepared for shipment in accordance with ASTM B 660 and in compliance with applicable rules and regulations pertaining to the handling, packaging, and transportation of the brazed parts to ensure carrier acceptance and safe delivery. 6. ACKNO
47、WLEDGMENT The processor shall mention this specification number and its revision letter in all quotations and when acknowledging purchase orders. 7. REJECTIONS Parts not brazed in accordance with this specification, or to modifications authorized by purchaser, will be subject to rejection.8. NOTES 8
48、.1 A change bar (|) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of a specification. An (R) symbol to the left of the document title indicates a complete revision of the specification, including technical revision. Change bars and (R) are not used in original publications, nor in specifications that contain editorial changes only. 8.2
