1、 ENGINEERING MATERIAL SPECIFICATIONDate Action Revisions 2010 09 28 N-STATUS No replacement G. Weber, NA 2003 07 31 Revised Para 3.0 inserted; Para 3.1, 3.9, 4 deleted 1996 02 29 Activated P. Lee Printed copies are uncontrolled Copyright 2010, Ford Global Technologies, Inc. Page 1 of 3 MOLYBDENUM AN
2、D NICKEL, CHROMIUM ALLOY FACING, WSE-M1P92-A1/A2 CO-DEPOSITED NOT TO BE USED FOR NEW DESIGN 1. SCOPE The material defined by this specification is a mixture of molybdenum and nickel-chromium hardening alloy powders, applied with a plasma spray gun. 2. APPLICATION This specification was released orig
3、inally for a facing applied to the surface of parts to obtain increased wear and scuff resistant properties. The original release of this specification is for deposition on the O.D. surface of cast iron piston compression rings in an internal combustion engine. 3. REQUIREMENTS 3.0 STANDARD REQUIREME
4、NTS FOR PRODUCTION MATERIALS Material suppliers and part producers must conform to the Companys Standard Requirements For Production Materials (WSS-M99P1111-A). 3.2 POWDER MIXTURE A1 A2 Molybdenum (99% min purity) 67 80% 55 75% Nickel Chromium Alloy 20 33% 21 33% (see para 3.2) Chrome Carbide (98% p
5、ure) 4 12% 3.3 NICKEL-CHROMIUM ALLOY CHEMISTRY Nickel 64.0 75.0 Chromium 13.0 20.0 Boron 2.75 4.75 Silicon 3.0 5.0 Iron 3.0 5.0 Cobalt 1.0 max Carbon 0.6 1.3 3.4 THICKNESS As specified on engineering drawing Material in sprayed and deposited condition is rough and uneven. Material is generally spray
6、ed to a thickness greater than required, and ground or lapped approximately 0.05 mm deep to specified thickness and surface finish. Thickness to be determined on a metallurgical cross section sample mounted and polished. ENGINEERING MATERIAL SPECIFICATIONWSE-M1P92-A1/A2 Printed copies are uncontroll
7、ed Copyright 2010, Ford Global Technologies, Inc. Page 2 of 3 3.5 SURFACE HARDNESS 320 min HV 0.5 (ISO 6507/2) 3.6 MICROSTRUCTURE The microstructure of the facing, on a metallurgical mounted and polished cross section, shall be a layered structure of uniformly distributed molybdenum and nickel-chrom
8、ium phases caused by the impact of molten particles upon the surface. Volume content and composition of the facing as determined by quantitative metallurgical system shall be as follows: A1 A2 Molybdenum, min 50% 40% Nickel Chromium, Chrome 20% 30% Carbide, min Porosity, max 15% 15% Occasional isola
9、ted unmelted particles are acceptable, however clusters of unmelted particles are not acceptable. Interphase fusion must be essentially complete, evidence of incomplete fusion or bonding between phases or phases or phases to base material is not acceptable. 3.7 COATING ADHESION 3.7.1 Cast Iron After
10、 shock loading the edge of the parts to cause the coating to rupture (such as a hammer blow upon the ring O.D. while resting flat on side on an anvil), the resulting fracture shall show failure only at the localized point of impact in the facing layer and no failure at the bond interface of the faci
11、ng with the base metal outside the deformed impact area. 3.7.2 Steel The bond quality is evaluated by subjecting the ring to sufficient mechanical deformation to cause the coating to separate from the groove. Subsequently the groove base is examined at 30X to determine coating surface area coverage.
12、 The minimum acceptable coverage representative of the separated area on the groove base is: A1 A2 70% 60% 3.8 QUALITY The deposited and ground or lapped facing shall possess a uniformly grayish appearance with no breaks, heavy pits or other imperfections that would detrimentally affect the part for
13、 the intended service. The surface shall not have pores greater than 0.51 mm in length or diameter in either direction and 75% of pores shall be less than 0.25 mm. ENGINEERING MATERIAL SPECIFICATIONWSE-M1P92-A1/A2 Printed copies are uncontrolled Copyright 2010, Ford Global Technologies, Inc. Page 3
14、of 3 5. GENERAL INFORMATION The information given below is provided for clarification and assistance in meeting the requirements of this specification. 5.1 CHEMICAL COMPOSITION OF FACING A1 A2 Molybdenum 65.0 80.0 50.0 70.0 Nickel 13.0 25.0 15.0 30.0 Chromium 2.5 7.0 5.0 15.0 Boron 0.5 2.0 0.5 2.0 Silicon 0.5 2.0 0.5 2.0 Iron 0.5 2.0 0.5 2.0 Carbon 0.1 1.0 0.5 2.0 5.2 PARTICLE HARDNESS OF LAYERED PHASES Molybdenum, HV 0.5 300 1,050 300 1,050 Nickel-Chromium, HV 0.5 350 1,400 350 1,400
