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 2017 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:/standards.sae.org/AMS2451/14 AEROSPACE MATERIAL SPECIFICATION AMS2451/14 Issued 2017-02 Plating, Brush, Nickel-Tu
5、ngsten Low Hydrogen Embrittlement RATIONALE AMS2451/14 results from the industry need for a specification for this process. 1. SCOPE 1.1 Purpose This specification covers the requirements for brush plating of nickel-tungsten by electrodeposition. 1.2 Application This process has been used as a chrom
6、ium alternative for repair and OEM applications that require exceptionally hard elcectroplated deposits. Its typically used to improve hardness and wearability and to repair damaged or worn parts, but usage is not limited to such applications. 1.3 Safety - Hazardous Materials Shall be in accordance
7、with AMS2451. 2. APPLICABLE DOCUMENTS Shall be in accordance with AMS2451. 3. TECHNICAL REQUIREMENTS Shall be in accordance with AMS2451 and as follows. 3.1 Procedure 3.1.1 Nickel-tungsten alloy plate shall be electrodeposited from a brush plating solution in accordance with processing instructions
8、from the solution manufacturer. 3.1.2 When specifically allowed by the cognizant engineering organization, the hydrogen embrittlement relief baking requirement of AMS2451 may be waived (see 8.3). 3.2 Properties Shall be in accordance with AMS2451 and as follows: SAE INTERNATIONAL AMS2451/14 Page 2 o
9、f 3 3.2.1 Composition The nickel-tungsten alloy deposit shall contain 38 to 45% tungsten and the balance nickel, determined by a method agreed upon by purchaser and processor. 3.2.2 Adhesion to Specimens Adhesion to specimens is required and shall be in accordance with AMS2451. 3.2.3 Hardness The ha
10、rdness of the deposit shall be not less than 675 HV or equivalent. 3.2.4 Stress The residual stress in the deposit shall be within the range of 30 ksi (206 MPa) tensile to 80 ksi (551 MPa) tensile. 3.2.5 Corrosion Resistance The requirements of AMS2451 shall apply except that salt spray exposure tim
11、e shall be 500 hours 1 hour. Specimens shall be plated to a thickness of 0.0004 to 0.0007 inch (10 to 18 micrometers), with a preplate or bonding layer of copper first, plated to a maximum thickness of 0.0002 inch (5 micrometers). 3.2.6 Hydrogen Embrittlement Shall be in accordance with AMS2451 exce
12、pt that when specifically allowed by the cognizant engineering organization, this test may be waived (see 8.2). 4. QUALITY ASSURANCE PROVISIONS Shall be in accordance with AMS2451 except as follows. 4.1 Periodic Tests Hydrogen embrittlement (3.2.6) is a periodic test and shall be performed at least
13、once each month that parts are processed, unless the solution is batch controlled and the batch has been previously tested and passed the hydrogen embrittlement test of AMS2451. Every batch of solution shall be tested in accordance with AMS2451 and given an expiration date or shelf-life from date of
14、 testing and be so noted on the solution container label. Tests of cleaning and plating solutions are periodic tests and shall be performed at a frequency established by the processor unless frequency of testing is specified by cognizant engineering organization. 5. PREPARATION FOR DELIVERY Shall be
15、 in accordance with AMS2451. 6. ACKNOWLEDGMENT Shall be in accordance with AMS2451. 7. REJECTIONS Shall be in accordance with AMS2451. SAE INTERNATIONAL AMS2451/14 Page 3 of 3 8. NOTES See AMS2451 and the following: 8.1 An acceptable rationale for exempting the processor from performance of hydrogen
16、 embrittlement relief baking and testing is for the processor to demonstrate that unbaked test specimens pass the hydrogen embrittlement relief test requirements of 4.2. The cognizant engineering organization should specify the procedure by which the processor may qualify for such an exemption and a
17、ny circumstances that may be cause for requalification. 8.2 Revision Indicator A change bar (l) 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 this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only. PREPARED BY AMS COMMITTEE “B”
