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 reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2011 SAE International All rights reserved. No part of this publication m
3、ay 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: +1 724-776-4970 (outside U
4、SA) 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/AMS2451C AEROSPACE MATERIAL SPECIFICATION AMS2451 REV. C Issued 1998-07 Revised 2011-07 Super
5、seding AMS2451B Plating, Brush General Requirements RATIONALE AMS2451C results from a Five Year Review and update of this specification. NOTICE ORDERING INFORMATION: The following information shall be provided to the plating processor by the purchaser. 1) Purchase order shall specify not less than t
6、he following: AMS2451 detail specification number and revision letter. Plating thickness desired. See 3.5.1. Basis metal to be plated. Tensile strength or hardness of the basis metal. Pre-plate stress relief to be performed by plating processor (time and temperature) if different from 3.3.1. Special
7、 features, geometry or processing present on parts that requires special attention by the plating processor. Hydrogen embrittlement relief to be performed by plating processor (parameters or reference document) if different from 3.4.3.1. Provisions peculiar to parts or assemblies to be repaired or o
8、verhauled. Optional: Periodic testing frequency (4.2.2) and sample quantity (4.3.2) if different from 4.2.2 and 4.3.2. Quantity of pieces to be plated. 2) Parts manufacturing operations such as heat treating, forming, joining and media finishing can affect the condition of the substrate for plating,
9、 or if performed after plating, could adversely affect the plated part. The sequencing of these types of operations should be specified by the cognizant engineering organization or purchaser and is not controlled by this specification. SAE AMS2451C Page 2 of 9 1. SCOPE 1.1 Purpose This specification
10、 and its supplementary detail specifications establish the requirements for electrodeposition of metals by brush plating. 1.2 Application This process has been used typically to improve surface properties such as corrosion resistance, wear resistance, and brazeability or to repair damaged, worn, or
11、mismachined parts, but usage is not limited to such applications. This process is particularly useful for plating localized areas on-site, especially on large parts or assemblies, and for minimizing masking. 1.3 Safety - Hazardous Materials While the materials, methods, applications, and processes d
12、escribed or referenced in this specification may involve the use of hazardous materials, 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 t
13、ake 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 work to a subs
14、equent revision of a document unless a specific document issue 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. 2.1 SAE Publications Available from SAE International, 400 Commonwealth
15、Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. AMS2759 Heat Treatment of Steel Parts - General Requirements AMS2759/9 Hydrogen Embrittlement Relief (Baking) of Steel Parts AS2390 Chemical Process Test Specimen Material 2.2 ASTM
16、 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 B 117 Operating Salt Spray (Fog) Testing Apparatus ASTM B 253 Preparation of Aluminum Alloys for Electroplating ASTM B 487 Measurements of Me
17、tal and Oxide Coating Thicknesses by Microscopical Examination of a Cross Section ASTM B 499 Measurement of Coating Thicknesses by the Magnetic Method: Nonmagnetic Coatings on Magnetic Basis Metal ASTM B 504 Measurement of Thickness of Metallic Coatings by the Coulometric Method SAE AMS2451C Page 3
18、of 9 ASTM B 530 Measurements of Coating Thicknesses by Magnetic Method: Electrodeposited Nickel Coatings on Magnetic and Nonmagnetic Substrates ASTM B 567 Measurement of Coating Thickness by the Beta Backscatter Method ASTM B 568 Measurement of Coating Thickness by X-Ray Spectrometry ASTM B 571 Adhe
19、sion of Metallic Coatings ASTM E 376 Measuring Coating Thickness by Magnetic-Field or Eddy-Current (Electromagnetic) Test Methods ASTM E 384 Knoop and Vickers Hardness of Materials ASTM F 519 Mechanical Hydrogen Embrittlement Testing of Plating Processes and Aircraft Maintenance Chemicals 3. TECHNIC
20、AL REQUIREMENTS 3.1 Detail Specification The requirements for a specific brush plating shall consist of all requirements specified herein in addition to requirements specified in the applicable detail specification. In case of conflict between requirements of this basic specification and the applica
21、ble detail specification, requirements of the detail specification shall govern. 3.2 Parts and test specimens shall be plated by trained operators who have been approved initially and periodically thereafter for plating on the basis material with the equipment and processing materials to be used. Op
22、erator training shall include plating of simulated parts and specimens, and approval shall be based on evaluation of the operators familiarity with the brush plating equipment/solutions, and the specification requirements. See 8.3. 3.3 Preparation 3.3.1 All steel parts having a hardness of 40 HRC an
23、d above and that are machined, ground, cold formed or cold straightened shall be cleaned to remove surface contamination and thermally stress relieved before plating for relief of residual tensile stresses. Temperatures to which parts are heated shall be such that maximum stress relief is obtained w
24、ithout reducing hardness of parts below drawing limits, but, unless otherwise specified, not less than 275 F (135 C) for not less than 5 hours for parts having hardness of 55 HRC or higher or not less than 375 F (191 C) for not less than 4 hours for other parts. Residual tensile stresses have been f
25、ound to be damaging during plating. 3.3.1.1 For parts, excluding nitrided parts, having a hardness of 55 HRC and above, including carburized and induction hardened parts, stress relieve at 275 F 25 (135 C 14) for a minimum of 5 hours. 3.3.1.2 For parts having a hardness less than 55 HRC, stress reli
26、eve at 375 F 25 (191 C 14) for a minimum of 4 hours. Nitrided parts fall into this category. Higher temperatures shall be used only when specified or approved by the cognizant engineering organization. 3.3.1.3 For peened parts: If stress relief temperatures above 375 F (191 C) are elected, the stres
27、s relieve shall be performed prior to peening or the cognizant engineering organization shall be consulted and shall approve the stress relief temperature. 3.3.1.4 Assemblies shall be treated in a manner acceptable to the cognizant engineering organization. 3.3.2 The plating shall be applied over a
28、surface free from water breaks. The cleaning procedure shall not produce pitting or intergranular attack of the basis metal and shall preserve dimensional requirements. 3.3.3 For parts that are to be plated all over, electrical contact locations shall be acceptable to purchaser. For parts that are n
29、ot to be plated all over, locations shall be in areas on which plating is not required. SAE AMS2451C Page 4 of 9 3.4 Procedure 3.4.1 The equipment, materials, and procedures used to process specimens and parts shall conform to a schedule of control factors (4.4.3) and to the recommendations of the m
30、anufacturer of the selective plating equipment and processing materials. 3.4.1.1 Aluminum alloys may be zincate or stannate treated in accordance with ASTM B 253 or other method acceptable to the cognizant engineering organization prior to plating. 3.4.2 After plating, parts shall be rinsed with wat
31、er, to remove residual plating solution, and immediately dried. 3.4.3 Post Treatment 3.4.3.1 Hydrogen Embrittlement Relief Treatment of steel parts shall be in accordance with AMS2759/9 except baking of parts plated in accordance with AMS2451/4, AMS2451/9, and AMS2451/10 is not required when complia
32、nce with 3.5.3.6 is achieved without baking. 3.4.3.2 Assemblies shall be treated in a manner acceptable to the cognizant engineering organization. 3.5 Properties The following requirements apply to all detail specifications. 3.5.1 Thickness Plating thickness shall be as specified on the drawing/purc
33、hase order and shall be in accordance with any of the following methods as applicable: ASTM E 376, ASTM B 487, ASTM B 499, ASTM B 504, ASTM B 530, ASTM B 567, ASTM B 568, or other method acceptable to the cognizant engineering organization. Unless otherwise specified, plating thickness shall be unif
34、orm within 20%, except within 1/8 inch (3.2 mm) of exterior edges and corners where thicker plating (buildup) is permissible. 3.5.1.1 Where “nickel flash” is specified, plate thickness shall be approximately 0.0001 inch (3 m). 3.5.2 Adhesion to Parts There shall be no visual evidence of plating sepa
35、ration from the underlying substrate when the following test is performed. Tape, 1-inch (25 mm) wide or wider, having adhesive strength of not less than 60 ounces per inch (0.66 N/mm) of width, shall be firmly applied to the plated area. It shall then be pulled manually from the plated area at appro
36、ximately 90 degrees to the plated surface in one sharp movement. When both unplated and plated areas can be covered by the tape, it shall be pulled from the unplated area toward the plated area. 3.5.2.1 When plating is to be subsequently machined, this test may be omitted if acceptable to the cogniz
37、ant engineering organization. 3.5.3 The following requirements only apply when specified in a detail specification. 3.5.3.1 Adhesion to Specimens Adhesion shall meet the requirements of ASTM B 571 by the Bend Test method. There shall be no evidence of separation of plating from the basis metal when
38、examined at 4X magnification; cracks which do not result in flaking or peeling of the plate are acceptable. 3.5.3.2 Hardness Hardness values shall be as specified and shall be determined in accordance with ASTM E 384. SAE AMS2451C Page 5 of 9 3.5.3.3 Stress The residual surface stress in the deposit
39、 shall be as specified in a detailed specification and shall be determined by X-Ray diffraction or another method which is acceptable to the cognizant engineering organization. 3.5.3.4 Heat Resistance 3.5.3.4.1 Plated ferrous and corrosion-resistant parts or specimens shall withstand without blister
40、ing, cracking, or debonding, being heated in air to 700 F 15 (371 C 8) and held at temperature for not less than 23 hours, followed by heating in air to 1000 F 15 (538 C 8) and holding at temperature for not less than 60 minutes, then air cooling to room temperature. 3.5.3.4.2 Plated aluminum and al
41、uminum-alloy, and copper and copper-alloy parts or specimens, shall pass the heat-quench test of ASTM B 571. 3.5.3.5 Corrosion Resistance Representative specimens shall be plated and post-plating treated as specified in a detail specification. There shall be no visual evidence of corrosion of the ba
42、sis metal on plated surfaces after continuous exposure to salt spray, in accordance with ASTM B 117, for 48 hours, -0, +1, unless another period is specified. Where plating is used only to aid brazing or where used only for dimensional restoration, corrosion testing may be waived if acceptable to th
43、e cognizant engineering organization. 3.5.3.6 Hydrogen Embrittlement The plating process shall not cause hydrogen embrittlement in steel parts 36 HRC and over determined in accordance with 4.3.3.3. 3.6 Quality To the unaided eye, the plating shall be continuous and free from plating defects such as
44、frosty areas, pin holes, blisters, porosity, nodules, and pits; slight staining or discoloration is permissible. Parts shall be free from evidence of arcing and of overheating. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The processor shall be responsible for performance of all
45、 tests and shall supply all specimens required for processors tests. When parts are to be tested, such parts shall be supplied by purchaser. The cognizant engineering organization reserves the right to sample and perform any confirmatory testing deemed necessary to ensure that plating conforms to sp
46、ecified requirements. 4.2 Classification of Tests 4.2.1 Acceptance Tests Thickness (3.4.1.1), adhesion to parts (3.4.1.2), and quality (3.5) are acceptance tests and shall be performed on each lot. SAE AMS2451C Page 6 of 9 4.2.2 Periodic Tests When required by the applicable detail specification, ad
47、hesion to specimens (3.5.3.1), hardness (3.5.3.2), stress (3.5.3.3), heat resistance (3.5.3.4) and corrosion resistance (3.5.3.5) are periodic tests and shall be performed at least quarterly unless frequency of testing is specified by the cognizant engineering organization. When required by the appl
48、icable detail specification, hydrogen embrittlement (3.5.3.6) is a periodic test and shall be performed at least once in each month that steel parts 36 HRC and over are plated to the applicable detail specification unless frequency of testing is specified by the cognizant engineering organization. T
49、ests of preparatory and plating solutions are periodic tests and shall be performed at a frequency established by the processor unless frequency of testing is specified by the cognizant engineering organization. 4.2.3 Preproduction Tests All property verification tests (3.4) are preproduction tests and shall be performed for each schedule of control factors prior to initial shipment of pl
