1、 ENGINEERING MATERIAL SPECIFICATION Date Action Revisions Rev. 05 2018 08 07 Released Re-Released A5 See Summary of Revisions J. Ulferts, NA 2014 10 30 Inactive A1 replaced by WSS-M1P95-A1; A2 replaced by WSS-M1P95-A2; A3 replaced by WSS-M1P95-A3; A4 replaced by WSS-M1P95-A4. No replacement for A5 a
2、nd A6 G. Weber, NA 1996 03 15 Activated P. Lee Controlled document at www.MATS Copyright 2018, Ford Global Technologies, LLC Page 1 of 3 PLATING, TIN/ZINC ALLOY, MECHANICALLY WSS-M1P93-A5 PLATED OVER FERROUS SURFACES 1. SCOPE This specification defines the requirements for mechanically plated deposi
3、ts that are subsequently E-coated. The material consists of an adherent copper flash, and a tin/zinc deposit. 2. APPLICATION This specification was released originally to define performance requirements for corrosion resistance. It was subsequently revised to define the plating for hardened self pie
4、rcing rivets used to join sheet metal. The tin provides lubricity during installation and plating provides sacrificial corrosion protection. 2.1 LIMITATIONS Due to the low melting point of tin-zinc alloy 197 C, the long term maximum service temperature is 180 C. 3. REQUIREMENTS 3.1 APPROVED SOURCES
5、This specification is performance based and does not have approved sources. 3.2 COATING APPLICATION Applicators shall follow material supplier procedures and recommendations for chemical usage, equipment, analysis, and processing. Applicators must have documentation to show that procedures and recom
6、mendations are followed. 3.2.1 Cleaning Prior to coating, the parts shall be free of oil, scale, and similar foreign materials. All parts must be degreased using alkaline cleaners and/or mechanically cleaned (shot blast). 3.2.2 Mechanical Plating Degreased parts are loaded together with water and gl
7、ass impact media into the open-ended mechanical plating barrel where an adherent layer of copper flash is applied. A flash coating is next applied to the parts by the addition of a small amount of zinc metal powder, after which sequential tin and zinc additions are made, the amounts of which are det
8、ermined by the desired coating thickness. 3.2.3 Water Polish Mechanically plated parts are water polished to remove loose surface particles and compact the coating. ENGINEERING MATERIAL SPECIFICATION WSE-M1P93-A5 Copyright 2018, Ford Global Technologies, LLC Page 2 of 3 3.2.4 Passivate The coating i
9、s not passivated or sealed. Should the formation of white corrosion products prior to installing the rivet be a concern, a passivate or sealer could be added and a new suffix added to the specification. 3.2.5 Appearance The coating shall be uniform in color and free from discontinuities when viewed
10、without magnification. 3.3 CHEMICAL COMPOSITION (ASTM B568, E634) Tin Zinc Weight % 20 - 40 60 - 80 3.4 PLATING THICKNESS Average (ASTM B659, ASTM B487) 8 m min Plating thickness requirements represents the average of at least 10 readings on a significant surface. Significant surfaces are defined as
11、 visible surfaces after installation. In case of dispute, the umpire method shall be metallographic sectioning per ASTM B487. 3.5 PLATING ADHESION (ASTM D3330) Test Method Apply a piece of tape onto the significant surface with firm pressure. Remove the tape within 90 +/- 30 seconds of application b
12、y pulling it off rapidly (not jerked) back upon itself at as close to an angle of 180 to the sample as possible. Tape shall have a minimum adhesion to steel of 23 oz./in. width (25 N/100mm) when tested per ASTM D3330. Acceptance Criteria No removal of the plating such that the substrate is exposed.
13、3.6 EMBRITTLEMENT The mechanical plating process defined in this specification does not contain an acid wash and meets the hydrogen embrittlement avoidance requirements in WSS-M99A3-A without the need for embrittlement relief. 3.7 CORROSION RESISTANCE (CETP 00.00-L-467) Self-piercing rivets No Requi
14、rement The rivets are installed in the body sheet metal prior to coating with E-coat primer. Corrosion testing after E-coat is more appropriate. Other applications requiring corrosion resistance must add a separate requirement. 4. GENERAL INFORMATION The information given below is provided for clari
15、fication and assistance in meeting the requirements of this specification. Contact for questions concerning Engineering Material Specifications. ENGINEERING MATERIAL SPECIFICATION WSE-M1P93-A5 Copyright 2018, Ford Global Technologies, LLC Page 3 of 3 4.1 PROCESS CONTROL ITEM, NEUTRAL SALT SPRAY (AS
16、TM B117) Neutral salt spray (NSS) testing is not acceptable for showing conformance to this specification. However, NSS testing is often used as a process control tool by plating applicators and as such may form part of the Control Plan. White Corrosion N/A Red Corrosion 96 hours min 4.2 RESTRICTED
17、SUBSTANCE MANAGEMENT STANDARD Substance restrictions imposed by regulations or Company direction applies to the materials addressed by this document. The restrictions are identified in the Restricted Substance Management Standard WSS-M99P9999-A1 which is updated yearly. It is the suppliers responsib
18、ility to comply with this standard on a continuing basis through IMDS and or GMAP reporting. 5. SUMMARY OF REVISIONS 2018 08 07 Returned A5 to Active status. Separated Electroplate (A1-A4) from mechanical plate (A5-A6). Removed WSS-M99P1111-A and added those requirements directly into the specificat
19、ion. Completely revised entire document and all requirements to latest levels. 2014 10 30 Inactive A1 replaced by WSS-M1P95-A1; A2 replaced by WSS-M1P95-A2; A3 replaced by WSS-M1P95-A3; A4 replaced by WSS-M1P95-A4. No replacement for A5 and A6 2010 10 07 N-Status A1 replaced by WSS-M1P95-A1; A2 repl
20、aced by WSS-M1P95-A2; A3 replaced by WSS-M1P95-A3; A4 replaced by WSS-M1P95-A4. No replacement for A5 and A6 2004 03 17 Returned to active status allowing only hex chrome free conversion coatings. 2004 01 28 N Status Hex chrome elimination initiative. Standard paragraph 3.0 inserted para 3.1, 3.6 and 4 deleted 1996 03 15 Released
