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 2012 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/AMS2400X AEROSPACE MATERIAL SPECIFICATION AMS2400 REV. X Issued 1940-01 Revised 2013-02 Super
5、seding AMS2400W Plating, Cadmium RATIONALE AMS2400X results from a Five Year Review and update of this specification and clarifies requirements for stress relief prior to plating and hydrogen embrittlement relief after plating on steel parts. NOTICE ORDERING INFORMATION: The following information sh
6、all be provided to the plating processor by the purchaser. 1) Purchase order shall specify not less than the following: AMS2400X Plating thickness desired. See 3.4.1 Basis metal to be plated Tensile strength or hardness of the basis metal Pre-plate stress relief to be performed by plating processor
7、(time and temperature) if different from 3.1.2 Special 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 3.4.4 Minimum thic
8、kness on internal surfaces, if required. See 3.4.1.4.1 Optional: Periodic testing frequency (4.2.2) and sample quantity (4.3.3) 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
9、plating, 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 AMS2400X Page 2 of 10 1. SCOPE 1.1 Purpose This spec
10、ification covers the requirements for electrodeposited cadmium on metal parts. 1.2 Application This process has been used typically to provide corrosion resistance to metal parts, but usage is not limited to such applications. 1.3 Safety-Hazardous Materials While the materials, methods, applications
11、, and processes described 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 m
12、aterials and to take necessary precautionary measures to ensure the health and safety of all personnel involved. 1.4 Warning This process uses cadmium as a plating material. The use of cadmium has been restricted and/or banned for use in many countries due to environmental and health concerns. The u
13、ser should consult with local officials on applicable health and environmental regulations regarding its use. 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 w
14、ork to a subsequent 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
15、Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. AMS2759/9 Hydrogen Embrittlement Relief (Baking) of Steel Parts AS2390 Chemical Process Test Specimen Material SAE AMS2400X Page 3 of 10 2.2 ASTM Publications Availabl
16、e 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) Apparatus ASTM B 253 Preparation of Aluminum Alloys for Electroplating ASTM B 487 Measurement of Metal and Oxide Coating Thickness
17、es by Microscopical Examination of a Cross Section ASTM B 499 Measurement of Coating Thicknesses by the Magnetic Method; Nonmagnetic Coatings on Magnetic Basis Metals ASTM B 504 Measurement of Thickness of Metallic Coatings by the Coulometric Method ASTM B 567 Measurement of Coating Thickness by the
18、 Beta Backscatter Method ASTM B 568 Measurement of Coating Thickness by X-Ray Spectrometry ASTM B 571 Qualitative Adhesion Testing of Metallic Coatings ASTM E 376 Measuring Coating Thickness by Magnetic-Field or Eddy-Current (Electromagnetic) Test Methods ASTM F 519 Mechanical Hydrogen Embrittlement
19、 Evaluation of Plating Processes and Service Environments 3. TECHNICAL REQUIREMENTS 3.1 Preparation 3.1.1 Parts shall be within drawing dimension limits before plating, except as specified in 3.1.1.1. 3.1.1.1 Parts having part numbers with the prefix AN, MA, MS, or AS, and required to be plated in a
20、ccordance with this specification, or parts where the drawing specifies that dimensions apply after plating, shall be made to such dimension that parts will be within drawing limits after plating. Undercutting before plating shall not be permitted unless specifically authorized by specifications ref
21、erenced on the applicable drawing. 3.1.2 Stress Relief Treatment All steel parts having a hardness of 36 HRC and above and that are machined, ground, cold formed or cold straightened after heat treatment shall be cleaned to remove surface contamination and thermally stress relieved before plating. (
22、Residual tensile stresses have been found to be damaging during electrofinishing.) Temperatures to which parts are heated shall be such that maximum stress relief is obtained while still maintaining hardness of parts within drawing limits. Unless otherwise specified, the following treatment temperat
23、ures and times shall be used: 3.1.2.1 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 5 to 10 hours. 3.1.2.2 For parts having a hardness less than 55 HRC, stress relieve at 375 F
24、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. 3.1.2.3 For peened parts: If stress relief temperatures above 375 F (191 C) are elected, the stress relieve sha
25、ll be performed prior to peening or the cognizant engineering organization shall be consulted and shall approve the stress relief temperature. SAE AMS2400X Page 4 of 10 3.1.3 Any specified residual compressive stress-inducing operations, such as shot peening, shall precede plating. 3.1.4 The plating
26、 shall be applied over a surface free from waterbreaks. The cleaning procedure shall not produce pitting or intergranular attack of the basis metal and shall preserve dimensional requirements. 3.1.4.1 Alkaline cleaning of steel parts may be done with anodic current, but steel parts over 36 HRC shall
27、 not be cathodically cleaned. 3.1.5 Except for barrel plating, electrical contact points shall be as follows. For parts which are to be plated all over, locations shall be specified or approved by the cognizant engineering organization. For parts which are not to be plated all over, locations shall
28、be in areas on which plating is not required, or locations shall be specified or approved by the cognizant engineering organization. 3.2 Procedure 3.2.1 Parts shall be plated by electrodeposition of cadmium from a suitable cadmium plating solution. 3.2.1.1 The cadmium shall be deposited directly on
29、the basis metal without a prior strike coating of other metal, such as copper or nickel underneath, except in the case of parts, assemblies, and weldments made wholly or in part of corrosion-resistant steel or similarly passive materials, on which a preliminary strike of nickel or other suitable met
30、al is permissible. 3.2.1.2 Aluminum alloys shall be zincate treated in accordance with ASTM B 253 or other method acceptable to the cognizant engineering organization prior to plating. 3.2.1.3 Brightening agents or other additives to the plating solution shall not be permitted for use on parts heat
31、treated to a hardness of 36 HRC or tensile strength of 160 ksi (1103 MPa) or higher. 3.2.2 After rinsing in water, and without allowing parts to dry, plated parts shall be given a supplementary coating, using a commercial chromate treatment; such parts shall meet the color requirements of 3.5.2.1. I
32、n lieu of the commercial chromate treatment, when permitted by the cognizant engineering organization, parts may be dipped, with agitation in a 3 to 5% solution of chromic acid to which small quantities of other inorganic acids may be added; such parts shall meet the color requirements 3.5.2.2. See
33、8.5. When plated parts require hydrogen embrittlement relief as in 3.3, surface reactivation and the supplementary treatment shall follow the hydrogen relief bake unless otherwise specified by the cognizant engineering organization. 3.2.3 The plated parts shall be removed from the chromic acid or ch
34、romate solution, thoroughly rinsed, and dried. 3.3 Hydrogen Embrittlement Relief (Baking) Treatment of steel parts shall be in accordance with AMS2759/9. except all parts plated per this specification HRC 36 and higher shall be baked. 3.4 Properties The plating shall conform to the following require
35、ments: 3.4.1 Thickness shall be as specified on the drawing, determined on representative parts or, when permitted by the cognizant engineering organization, on test panels in accordance with any of the following methods as applicable: ASTM B 487, ASTM B 499, ASTM B 504, ASTM B 567, ASTM B 568, ASTM
36、 E 376, or other method permitted by the cognizant engineering organization. 3.4.1.1 Plate thickness may be specified by AMS2400 and a suffix number normally designating the minimum thickness in ten-thousandths of an inch; except as indicated in Table 1, the maximum plate thickness shall be 0.0002 i
37、nch (5 m) greater than the minimum. Thus AMS2400-2 designates a thickness of 0.0002 to 0.0004 inch (5 to 10 m) and AMS2400-6 designates a thickness of 0.0006 to 0.0008 inch (15 to 20 m). SAE AMS2400X Page 5 of 10 3.4.1.1.1 Plate thickness, when specified by AMS2400 and a suffix number, shall be as s
38、pecified in Table 1 for the specified suffix number and type of part or surface. 3.4.1.2 Where “cadmium flash” is specified, plate thickness shall be approximately 0.0001 inch (2.5 m). 3.4.1.3 The plate shall be substantially uniform in thickness on significant surfaces except that slight build-up o
39、n exterior corners or edges will be permitted provided finished drawing dimensions are met. 3.4.1.4 No requirements are established for minimum plate thickness on surfaces of holes, recesses, and internal threads except as specified in Table 1, contact areas of parts plated all over, and other areas
40、 where a controlled deposit cannot be obtained under normal plating conditions, but such areas shall not be masked to prevent plating. Except as specified in Table 1 for externally threaded sections, the resultant thickness shall be considered only when such surfaces of parts can be touched by a sph
41、ere 0.75 inch (19.0 mm) in diameter, however, such surfaces shall show visual evidence of coverage. 3.4.1.4.1 If internal surfaces as defined in 3.4.1.4 are required to be plated to a specified thickness, notes on the drawing will so specify. TABLE 1A - PLATE THICKNESS AND SALT SPRAY CORROSION RESIS
42、TANCE REQUIREMENTS, INCH/POUND UNITS AMS2400 Thickness Designation Specified External Threads Thickness Inch External Threads Salt Spray Resistance Hours, min Nuts, Washers, and Unthreaded Surfaces of Parts Externally Threaded Thickness Inch Nuts, Washers, and Unthreaded Surfaces of Parts Externally
43、 Threaded Salt Spray Resistance Hours, min Parts Not Externally Threaded Except Nuts and Washers Thickness Inch Parts Not Externally Threaded Except Nuts and Washers Salt Spray Resistance Hours, min 2400 0.0001 to 0.0004 100 0.0002 to 0.0005 150 0.0003 to 0.0005 200 2400-1 0.0001 to 0.0003 100 0.000
44、2 to 0.0004 150 0.0001 to 0.0003 100 2400-2 0.0001 to 0.0004 100 0.0002 to 0.0004 150 0.0002 to 0.0004 150 2400-3 0.0002 to 0.0005 150 0.0003 to 0.0005 200 0.0003 to 0.0005 200 2400-4 0.0003 to 0.0006 200 0.0004 to 0.0006 225 0.0004 to 0.0006 225 2400-5 0.0004 to 0.0007 225 0.0005 to 0.0007 250 0.00
45、05 to 0.0007 250 Note: For thickness designations AMS2400-X is greater than 5, plate thickness in ten-thousandths of an inch shall be X to X + 2 except on external threads where the plate thickness shall be X-1 to X+2; such parts shall withstand salt spray for not less than 250 hours. SAE AMS2400X P
46、age 6 of 10 TABLE 1B - PLATE THICKNESS AND SALT SPRAY CORROSION RESISTANCE REQUIREMENTS, SI UNITS AMS2400 Thickness Designation Specified External Threads Thickness Millimeter External Threads Salt Spray Resistance Hours, min Nuts, Washers, and Unthreaded Surfaces of Parts Externally Threaded Thickn
47、ess Millimeter Nuts, Washers, and Unthreaded Surfaces of Parts Externally Threaded Salt Spray Resistance Hours, min Parts Not Externally Threaded Except Nuts and Washers Thickness Millimeter Parts Not Externally Threaded Except Nuts and Washers Salt Spray Resistance Hours, min 2400 0.002 to 0.010 10
48、0 0.005 to 0.013 150 0.008 to 0.013 200 2400-1 0.002 to 0.008 100 0.005 to 0.010 150 0.002 to 0.008 100 2400-2 0.002 to 0.010 100 0.005 to 0.010 150 0.005 to 0.010 150 2400-3 0.005 to 0.013 150 0.008 to 0.013 200 0.008 to 0.013 200 2400-4 0.008 to 0.015 200 0.010 to 0.015 225 0.010 to 0.015 225 2400
49、-5 0.010 to 0.018 225 0.013 to 0.018 250 0.013 to 0.018 250 Note: For thickness designations AMS2400-X where X is greater than 5, plate thickness in millimeters shall be 0.0025X to 0.0025 (X+2) except on external threads where the plate thickness shall be 0.0025 (X-1) to 0.0025 (X+2); such parts shall withstand salt spray for not less than 250 hours. 3.4.2 Adhesion Plating shall be firmly adhered to the bas
