1、 ENGINEERING MATERIAL SPECIFICATIONDate Action Revisions 2006 07 20 Revised WSD-M8A19-A1/A2 and WSS-M8A19-A3 were inactivated and removed; No replacement named G. Weber2003 10 10 Revised Para 3.0 inserted; para 3.1, 3.8 and 4 deleted 1991 03 26 Released C10128523 N. Riley EAO, P. Lee NAO Printed cop
2、ies are uncontrolled Copyright 2006, Ford Global Technologies, Inc. Page 1 of 2 BEARINGS, ALUMINUM SILICON STEEL BACKED WSS-M8A19-A4 1. SCOPE The materials defined by this specification are aluminum-silicon bearing alloys bonded to a low carbon steel backing. 2. APPLICATION This specification was re
3、leased originally for material used in the manufacture of bearings and bushings for automotive applications. Uses include crank main, connecting rod, balance shaft and thrust washer bearings and bushings of medium load. 3. REQUIREMENTS Material specification requirements are to be used for initial q
4、ualification of materials. 3.0 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material suppliers and part producers must conform to the Companys Standard Requirements For Production Materials (WSS-M99P1111-A). Part producers using this material in their products, must use Ford approved materials and
5、 must conform to a process control plan which has been approved by STA and/or the relevant Materials Activity. 3.2 CONSTRUCTION The functional layer shall be cast or sintered into a wrought strip and roll-bonded onto a prepared steel backing (bonding coatings of nickel or aluminum up to 75 micromete
6、rs thickness allowed). Layer and backing thicknesses as stated on relevant Engineering drawing. 3.3 CHEMICAL COMPOSITION (weight %) 3.3.1 Steel Backing Cold rolled low carbon steel (0.03 - 0.25% carbon). ENGINEERING MATERIAL SPECIFICATIONWSS-M8A19-A4Printed copies are uncontrolled Copyright 2006, Fo
7、rd Global Technologies, Inc. Page 2 of 2 3.3.2 Functional Layer Tin 8.0 - 10.8 Copper 0.7 - 0.9 Iron 0.7 max Silicon 2.2 - 2.8 Chromium .15 - .25 Lead 0.2 max Manganese - Total Others 0.50 max Aluminum Balance 3.4 ADHESION The bond between the bearing layer and the steel backing must withstand the f
8、ollowing test: A sharp chisel with a cutting width of 10 mm minimum and a cutting angle of 40 - 50 will be forced at an angle of 30 - 60 between the bearing layer and the steel backing. The cutting motion of the chisel is in a direction which tends to pull the bearing layer away from the backing. Th
9、e bearing layer must not flake or spall. 3.5 HARDNESS (The average of 5 determinations minimum on the bimetal strip) (ASTM E 92/ASTM E 10) HV 49 minimum or HB 45 minimum Note: The maximum hardness will be part of the Control Plan, and shall be stated on Engineering Drawing following sample manufactu
10、re. 3.6 MICROSTRUCTURE The functional layer consists of a uniform distribution of silicon particles in an aluminum rich solid solution matrix, and shall be bonded to the steel backing with no bonding or interface defects when viewed at 100 times magnification. No silicon particle shall have any dime
11、nsion greater than 15 microns. This specification shall have no lead constituents. 3.7 MECHANICAL PROPERTIES The mechanical properties of the steel backing shall be controlled directly or indirectly (e.g. hardness) as part of the control plan to ensure consistent installation and functional characteristics.
