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/AMS2673E AEROSPACE MATERIAL SPECIFICATION AMS2673 REV. E Issued 1960-06 Reaffirme
5、d 2006-04 Revised 2012-01 Superseding AMS2673D Brazing, Aluminum and Aluminum Alloys Molten Flux (Dip) RATIONALE AMS2673E 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 of aluminum and alum
6、inum alloys by immersion in a molten flux bath. 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
7、 the use of hazardous materials, this specification does not address the hazards that 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
8、 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 work to a subsequent revision of a document unless a specific document i
9、ssue is specified. When the referenced document has been cancelled and no superseding document has been specified, the last published issue of that document shall apply. SAE AMS2673E Page 2 of 7 2.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001,
10、 Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. AMS3415 Flux, Aluminum Dip Brazing, 1030 F (554 C) or Lower Liquidus 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
11、.25Mn - 0.12Cu (No. 12-0 Brazing Sheet), Annealed 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 - 0.28Cu (No. 22 Brazing Sheet
12、), 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 3. TECHNICAL REQUIREMENTS 3.1 Materials 3.1.1 Filler metal sh
13、all be aluminum brazing alloy conforming to AMS4185 except as specified in 3.3.2. 3.1.2 Flux shall conform to AMS3415 or other suitable flux. 3.2 Equipment 3.2.1 Preheat furnace shall be maintained within the range 900 to 1050 F (482 to 566 C). 3.2.2 Salt-bath furnace shall be a ceramic-type maintai
14、ned within 10 F (6 C) of a selected temperature within the range 1050 to 1200 F (566 to 649 C). 3.3 Preparation 3.3.1 Surface Condition Surfaces to be joined shall be free from water breaks prior to assembly. See 8.2. 3.3.2 Assembly Clearances between mating surfaces of detail parts to be brazed sha
15、ll be held within specified tolerances. The assembly shall be supported so that the parts will be in proper alignment throughout brazing. Jigs, fixtures, and clamps shall be fabricated from material that will not significantly contaminate the flux bath. Stop-off may be used provided it does not cont
16、aminate the molten flux bath. On closed assemblies, vent holes shall be provided as specified. Except when parts are fabricated from clad brazing sheet such as AMS4063, AMS4064, AMS4255, or AMS4256, the filler metal shall be positioned at one end of the joint. Filler metal shall be placed at the bli
17、nd end of each blind joint when accessible. 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 the intended mating surfaces. SAE AMS2673E Page 3 of 7 3.3.3 Tack welding shall be use
18、d only when specified or permitted by purchaser. 3.4 Joining Assembled details shall be preheated in a furnace to an established temperature within the range 900 to 1050 F (482 to 566 C) and transferred immediately into the molten flux bath. Temperature of the flux bath shall be maintained within 10
19、 Fahrenheit (6 Celsius) degrees of a temperature established so as to preclude incipient melting, excessive alloying of the joint, and distortion in excess of dimensional requirements. Time in flux bath should be established using a pilot assembly in order to ensure complete filler metal penetration
20、 through the joint and limiting excessive alloying or erosion. 3.4.1 Cooling After brazing, assemblies shall be cooled in a manner that prevents cracks and minimizes internal stress, distortion, scaling, and oxidation. If solution heat treatment is to be performed in conjunction with brazing, coolin
21、g procedures may be revised accordingly. 3.5 Flux Removal After brazing and cooling, flux shall be removed by a method that is not injurious to the surface finish and that will not remove metal below the drawing tolerances. The test of 3.6.5 shall be used to determine that flux has been adequately r
22、emoved. 3.6 Properties Brazed assemblies shall conform to the following requirements: 3.6.1 Appearance Examination of the visible joint edges shall show a complete line or ring of filler metal between component parts at both ends of the joint. 3.6.1.1 The total accumulated length of any pinhole, voi
23、d (within braze filler), or filler metal skip (no presence of braze filler), extending 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 parent metal are not
24、 acceptable. 3.6.1.3 Overheating resulting in blisters on the base metal or eutectic melting is not acceptable. 3.6.1.4 Residual flux is not permissible on surfaces of the assembly. 3.6.2 Coverage Unless otherwise specified, the area joined by filler metal shall be not less than 80% of the area of t
25、he mating portions of the assembly, determined by a method acceptable to purchaser. 3.6.3 Proof Pressure Test When specified, any part from a lot shall pass a proof pressure test. Standards for acceptance and method of test shall be specified by purchaser. 3.6.4 Melting or erosion shall not cause th
26、inning of the parent metal surface adjacent to the brazed joint in excess of 5 percent of the parent metal thickness and 15 percent cumulative of the braze length. SAE AMS2673E Page 4 of 7 3.6.5 Halide Test Testing shall be conducted to ensure that residual flux has been removed. If the test indicat
27、es flux residue, the assemblies shall be subjected to additional cleaning and testing until flux removal is complete. In case of dispute, the procedure 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) reagent water (8.3
28、). Collect rinse water in a 100 mL beaker and add 3 to 5 drops of concentrated nitric acid (specific gravity 1.42) and 2 to 3 mL of 10 percent silver nitrate solution. Stir the contents of the beaker and allow to stand for 5 to 10 minutes. A resultant solution as clear as a blank of reagent water tr
29、eated in the same manner as the rinsings indicates the absence of chlorides. A white-to-gray precipitate or turbidity indicates the presence of residual flux. 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 rinse
30、water in a 250 mL beaker. Use approximately 200 mL of ASTM D 1193, Type IV, water as a blank or comparison sample. Both samples shall be tested in accordance with ASTM D 1179. A higher concentration of fluoride in the rinse water than in the blank or comparison sample indicates the presence of fluor
31、ide-containing residual flux. 3.7 Quality Brazed joints shall be sound, clean, free of unmelted filler metal in the joint, and free from other imperfections detrimental to performance of brazed joints. Filler metal in excess of that required for the joint is acceptable provided it does not interfere
32、 with form, fit, or function of the completed assembly. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The processor of brazed assemblies shall supply all test specimens for processors tests and shall be responsible for performing all required tests. Parts, when required for test,
33、 shall be supplied by 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 Classification of Tests 4.2.1 Acceptance Tests Flux removal (3.5), appearance (3.6.1), coverage (3.6.2),
34、and quality (3.7) are acceptance tests and shall be performed on brazed 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
35、 (3.6.2), and melting or erosion (3.6.4) are periodic tests and shall be performed at a frequency established by the processor unless frequency of testing is specified by purchaser. 4.2.3 Preproduction Tests All property verification tests (3.6) are preproduction tests and shall be performed prior t
36、o or on the initial shipment of brazed assemblies to the purchaser and when purchaser requires confirmatory testing. SAE AMS2673E Page 5 of 7 4.3 Sampling for Testing 4.3.1 Acceptance Tests Acceptance test samples shall be randomly selected from all parts or assemblies in the lot. A lot shall be all
37、 assemblies of the same part number brazed in a continuous operation and presented for processors inspection at one time. Unless the cognizant engineering organization provides a sampling plan, the minimum number of samples shall be as shown in Table 1. TABLE 1 - SAMPLING FOR ACCEPTANCE TESTING Numb
38、er of Parts in Lot Quantity and Appearance Coverage Non-Destructive 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 Pe
39、riodic Tests Sample quantities shall be selected at the discretion of the processor, unless otherwise specified by the cognizant engineering organization. 4.3.3 Preproduction Tests One joint shall be destructively examined for braze coverage and for evidence of overheating or other deleterious effec
40、ts. 4.4 Approval 4.4.1 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. 4.4.2 If the processor makes a change to any material, process, or control
41、 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 that, in the judgm
42、ent of the cognizant engineering organization could affect the properties or performance of the brazed parts. 4.4.2.1 Control factors include, but are not limited to, the following: Method of cleaning Brazing flux used Braze filler metal Placement of filler metal Preheat temperature and time Brazing
43、 cycle Method of flux removal Periodic test plan. SAE AMS2673E Page 6 of 7 4.5 Reports The processor of brazed assemblies shall furnish with each shipment a report stating that the assemblies have been brazed and tested in accordance with specified requirements and that they conform to other technic
44、al requirements. The report shall state the filler metal used, flux used, and, where proof pressure tests are required, the method of proof testing and results of all such tests. This report shall include the purchase order number, lot number, AMS2673E, part number, and quantity. 4.6 Resampling and
45、Retesting 4.6.1 If any acceptance test fails to meet the specified requirements, all assemblies shall be inspected for the nonconforming attribute. Assemblies that conform to requirements shall be accepted; assemblies that are nonconforming may be reworked as required or shall be subject to rejectio
46、n. 4.6.2 If the results of any periodic or destructive test fail to meet the specified requirements, the process is nonconforming. No additional assemblies shall be brazed until the process is corrected and new specimens are brazed and tested. Results of all tests shall be recorded, and when request
47、ed, reported. Purchaser shall be notified of all assemblies brazed since the last acceptable test. 5. PREPARATION FOR DELIVERY 5.1 Brazed assemblies shall be handled and packaged to ensure that the required physical characteristics and properties of the joints are preserved. 5.2 Packages of brazed a
48、ssemblies shall be prepared for shipment in accordance with commercial practice and in compliance with applicable rules and regulations pertaining to the handling, packaging, and transportation of the assemblies to ensure carrier acceptance and safe delivery. 6. ACKNOWLEDGMENT Processor shall mentio
49、n this specification number and its revision letter in all quotations and when acknowledging purchase orders. 7. REJECTIONS Assemblies not brazed in accordance with this specification, or with modifications authorized by purchaser will be subject to rejection. 8. NOTES 8.1 A change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial
