SAE AMS 2672G-2012 Brazing Aluminum Torch or Furnace《钎焊 铝火焰或熔炉》.pdf

1、_ SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising there

2、from, is the sole responsibility of the user.” 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 2012 SAE International All rights reserved. No part of this p

3、ublication may be reproduced, stored in 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: +1 724-776-497

4、0 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/AMS2672G AEROSPACE MATERIAL SPECIFICATION AMS2672 REV. G Issued 1949-11 Reaffirme

5、d 2006-04 Revised 2012-01 Superseding AMS2672F Brazing, Aluminum Torch or Furnace RATIONALE AMS2672G results from a Five Year Review and update of this specification. 1. SCOPE 1.1 Purpose This specification covers the requirements for producing brazed joints on aluminum and aluminum alloys by torch

6、or furnace brazing. 1.2 Application This process has been used typically for joining aluminum and selected aluminum alloys. 1.3 Safety - Hazardous Materials While the materials, methods, applications, and processes described or referenced in this specification may involve the use of hazardous materi

7、als, 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 materials and to take necessary precautionary measures to ensure the health and safety of all personne

8、l 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 work to a subsequent revision of a document unless a specific document issue is specified. When the

9、 referenced document has been cancelled and no superseding document has been specified, the last published issue of that document shall apply. SAE AMS2672G Page 2 of 7 2.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside

10、USA and Canada) or 724-776-4970 (outside USA), www.sae.org. AMS3412 Flux, Aluminum Brazing, for Torch or Furnace Brazing AMS4063 Aluminum Alloy, Clad One Side, Sheet, 1.25Mn - 0.12Cu, (No. 11-0 Brazing Sheet), Annealed AMS4064 Aluminum Alloy, Clad Two Sides Sheet, 1.25Mn - 0.12Cu, (No. 12-0 Brazing

11、Sheet), Annealed AMS4184 Filler Metal, Aluminum Brazing, 10Si - 4.0Cu (4145) AMS4185 Filler Metal, Aluminum Brazing, 12Si (4047) AMS4255 Aluminum Alloy, Clad One Side Sheet, 0.6Mg - 0.35Si - 0.28Cu (No. 21 Brazing Sheet), As Fabricated AMS4256 Aluminum Alloy, Clad Two Sides Sheet, 0.6Mg - 0.35Si - 0

12、.28Cu (No. 22 Brazing Sheet), As Fabricated 2.2 ASTM Publications Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM D 1179 Fluoride Ion In Water ASTM D 1193 Reagent Water 2.3 AWS Publications Available fro

13、m American Welding Society, 550 NW LeJeune Road, Miami, Florida 33126, Tel: 1-800-443-9353, www.aws.org. AWS B2.2 Brazing Procedures and Performance Qualification 3. TECHNICAL REQUIREMENTS 3.1 Materials 3.1.1 Filler metal shall be aluminum brazing alloy conforming to AMS4184 or AMS4185. 3.1.2 Flux F

14、lux for torch brazing or circulating-air type furnace brazing shall conform to AMS3412. 3.2 Equipment and Personnel 3.2.1 Torch Method Torches, tips, regulators, and accessory equipment shall be appropriate for the thickness of the material being brazed. 3.2.2 Furnace Method Furnaces shall be circul

15、ating-air type, maintained within 10 Fahrenheit (6 Celsius) degrees of a selected temperature within the range 900 to 1200 F (482 to 649 C) by suitable controls. SAE AMS2672G Page 3 of 7 3.2.3 Personnel Those engaged in torch brazing shall be tested periodically for proficiency in accordance with AW

16、S B2.2 or other procedure acceptable to purchaser. 3.3 Preparation 3.3.1 Surface Condition The surfaces to be joined shall be clean prior to assembly. Cleaning should be by degreasing using a suitable solvent, alkaline cleaning, and deoxidizing followed by a cold and hot water rinse. 3.3.2 Fluxing F

17、lux shall be applied so that surfaces to be joined are sufficiently coated to ensure the specified bond between the parts after brazing; if preplaced filler metal inserts are used, they shall also be coated with flux. 3.3.3 Assembly The parts to be joined shall be assembled so that clearances betwee

18、n mating surfaces are within specified tolerances. The assembly shall be supported so that the parts will be in proper alignment throughout brazing. Except when parts are fabricated from clad brazing sheet, such as AMS4063, AMS4064, AMS4255, or AMS4256, the filler metal as in 3.1.1 shall be preposit

19、ioned or fed in at one end of the joint. For a blind joint, the filler metal shall be placed at the blind end when access permits. When specified, filler metal may be placed within the joint prior to assembly for brazing. When parts are made from clad sheet, the clad surface shall be in contact with

20、 the intended mating surface. 3.3.3.1 Tack welding for fixturing shall be used only when specified or permitted by purchaser. 3.3.3.2 On closed assemblies, vent holes shall be provided as specified. 3.3.3.3 When desirable, flow of filler metal may be restricted by employing a paste compound of sodiu

21、m fluoride and water. 3.4 Procedure 3.4.1 Joining Joining shall be effected by torch or furnace heating. Parts shall be heated rapidly until the filler metal melts and joints are formed. The temperature to which parts are heated for brazing shall be controlled so that incipient melting of the parts

22、does not occur. 3.4.1.1 Torch Method Parts shall be heated locally in the joint area using a reducing flame, taking care not to overheat the parent metal. Sufficient filler metal shall be introduced to the joint. Parts shall be held at heat until clean filler metal is visible at the end of the joint

23、 opposite that at which the filler metal was introduced, when joint configuration permits visual examination during brazing. 3.4.1.2 Furnace Method Preheating to approximately 400 F (204 C) is recommended to remove any water from the flux or parts. The brazing time and temperature shall be such that

24、 clean filler metal is visible at the end of the joint opposite that at which the filler metal was introduced, when joint configuration permits such visual examination. The time and temperature necessary to obtain acceptable joints should be established through the use of a pilot assembly. SAE AMS26

25、72G Page 4 of 7 3.4.2 Cooling After brazing, assemblies shall be cooled in a manner which prevents cracks and minimizes internal stress, distortion, and oxidation. If solution heat treatment is to be done in conjunction with brazing, cooling procedures may be revised accordingly. 3.5 Flux Removal Af

26、ter brazing and cooling, flux shall be removed by a method which is not injurious to the surface finish and which will not remove basis material below drawing tolerances. The test in 3.6.5 shall be used to determine the adequacy of flux removal. 3.6 Properties Brazed parts and assemblies shall confo

27、rm to the following requirements: 3.6.1 Appearance Examination of visible joint edges shall show a complete line or ring of filler metal between component parts. 3.6.1.1 The total accumulated length of any pinholes, voids (within line of braze), or filler metal skips (no presence of braze) extending

28、 into the joint shall not exceed 10% of the total length of the fillet. Individual pinholes, voids, or filler metal skips shall not exceed 3/32 inch (2.4 mm). 3.6.1.2 Cracks in filler metal or adjacent parent metal are not acceptable. 3.6.1.3 Overheating, resulting in blisters on the base metal or e

29、utectic melting is not acceptable. 3.6.1.4 Residual flux is not permissible on surfaces of the part. 3.6.2 Coverage Unless otherwise specified, the area joined by the filler metal shall be not less than 80% of the area of the mating portions of the assembly, determined by a method agreed upon by pur

30、chaser and processor. 3.6.3 Proof Pressure Test When specified, any part from a lot shall pass a proof test. Standards for acceptance and method of test shall be as specified by purchaser. 3.6.4 Melting or erosion shall not cause thinning of the parent metal surface adjacent to the brazed joint in e

31、xcess of 5% of parent metal thickness and 15% cumulative of the braze length. 3.6.5 Halide Test Testing shall be conducted to ensure that residual flux has been removed. If the test indicates presence of flux residue, the parts shall be subjected to additional cleaning and testing until removal is c

32、omplete. In case of dispute, the procedures of 3.6.5.1 and/or 3.6.5.2 shall be used. 3.6.5.1 Chlorides Rinse the test area with 40 to 50 mL of hot approximately 180 F (82 C) ASTM D 1193, Type IV, water. Collect rinse water in a 100 mL beaker and add 3 to 5 drops of concentrated nitric acid (specific

33、 gravity 1.42) and 2 to 3 mL of 10% silver nitrate solution. Stir the contents of the beaker and allow to stand 5 to 10 minutes. A solution as clear as a blank of ASTM D 1193, Type IV, water treated in the same manner as the rinsings indicates the absence of chlorides. A white-to-gray precipitate or

34、 turbidity indicates the presence of residual flux. SAE AMS2672G Page 5 of 7 3.6.5.2 Fluorides Rinse the test area with approximately 200 mL of hot approximately 180 F (82 C) ASTM D 1193, Type IV, water. Collect the rinse water in a 200 mL beaker. Using two 100 mL Nessler, or equivalent, color compa

35、rison tubes, pour 100 mL of rinsings into one tube and 100 mL of ASTM D 1193, Type IV, water, into the other as a blank. Treat the water in the two tubes in accordance with ASTM D 1179, Method B, or use an equivalent colorimetric method. Allow the color to develop. A color in the rinse water deeper

36、than that of the blank indicates the presence of residual flux. 3.7 Quality Brazed joints shall be sound, clean, and free from foreign materials and from imperfections detrimental to performance of the brazed joints. Filler metal in excess of that required for the joint is acceptable provided it doe

37、s not interfere with form, fit, or function of the completed assembly. 3.7.1 The presence of unmelted filler metal in a joint is not acceptable. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The processor of brazed parts shall supply all samples for processors tests and shall be

38、responsible for the performance of all required tests. Parts, if required for tests, shall be supplied by purchaser. Unless otherwise specified, the processor may use his own or any other inspection facilities and services acceptable to purchaser. Purchaser reserves the right to sample and to perfor

39、m any confirmatory testing deemed necessary to ensure that the processing conforms to the requirements of this specification. 4.2 Classification of Tests 4.2.1 Acceptance Tests Flux removal (3.5), appearance (3.6.1) coverage (3.6.2) and quality (3.7) are acceptance tests and shall be performed on br

40、azed parts or assemblies sampled from each lot. See 4.3.1. 4.2.2 Periodic Tests Proof pressure testing when specified (3.6.3), destructive coverage testing when agreed upon by purchaser and processor when there exists a lot size of 40 or less (3.6.2), and melting or erosion (3.6.4) are periodic test

41、s and shall be performed at a frequency selected by the processor unless otherwise specified. 4.2.3 Preproduction Tests All property verification tests (3.6) are preproduction tests and shall be performed prior to or on the initial shipment of brazed parts to a purchaser and when purchaser deems con

42、firmatory testing to be required. 4.3 Sampling for acceptance testing shall be as shown in Table 1. A lot shall be all parts of the same part number brazed in a continuous operation and presented for processors inspection at one time. 4.3.1 Acceptance Tests Test samples shall be randomly selected fr

43、om all parts or assemblies in the lot. Unless the cognizant engineering organization provides a sampling plan, the minimum number of samples shall be as shown in Table 1. SAE AMS2672G Page 6 of 7 TABLE 1 - SAMPLING FOR ACCEPTANCE TESTING Number of Parts in Lot Quality and Appearance Coverage Nondest

44、ructive Tests Coverage Destructive Tests 1 to 6 7 to 15 16 to 40 41 to 110 111 to 300 301 to 500 501 to 700 701 to 1200 Over 1200 all all all all all all all all all 3 or all* 4 4 5 6 7 8 10 15 0 0 0 1 2 3 5 7 10 *Whichever is less 4.3.2 Periodic Tests Sample quantities shall be selected at the disc

45、retion of the processor, unless otherwise specified by the cognizant engineering organization. 4.4 Approval 4.4.1 Brazing by torch method shall be performed only by operators who have been qualified, by a procedure acceptable to purchaser, to braze the alloy specified for each part. See 3.2.3. 4.4.2

46、 The process and control procedures, a preproduction sample brazed part, or both, whichever is specified, shall be approved by the cognizant engineering organization before production parts are supplied. 4.4.3 If the processor of brazed parts makes a significant change in any brazing condition or co

47、ntrol factor, from that which was used for approval, all preproduction tests shall be performed and the results submitted to the cognizant engineering organization for process reapproval, unless the change is approved by the cognizant engineering organization. A significant change is one which, in t

48、he judgment of the cognizant engineering organization, could affect the properties or performance of the brazed parts. 4.4.3.1 Controls factors include, but are not limited to, the following: Method of cleaning Method of holding parts during brazing Type of filler metal Placement of filler metal Pre

49、heat time/temperature (furnace brazing) Braze time/temperature (furnace brazing) Method of flux removal Periodic test plan. 4.5 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 other technical requirements. This report shall include