1、 ENGINEERING MATERIAL SPECIFICATION Date Action Revisions Rev 03 2012 03 06 N Status No replacement or usage G. Weber, NA 2003 10 15 Revised Para 3.0 inserted; para 3.1, 3.7 and 4 deleted 1989 09 28 SM/ER8821TC Released W. Jones, N. Riley Controlled document at www.MATS Copyright 2012, Ford Global T
2、echnologies, Inc. Page 1 of 2 SINTERED IRON, LOW ALLOY, HIGH SPEED, WSD-M10A88-A INFILTRATED NOT TO BE USED FOR NEW DESIGN 1. SCOPE The material defined by this specification is a composite high speed steel with copper infiltration. 2. APPLICATION This specification was released originally for mater
3、ial used for exhaust valve seat inserts of internal combustion engines. Applications also may include intake and exhaust valve seat for diesel and internal combustion engines. 3. REQUIREMENTS 3.0 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material suppliers and part producers must conform to the
4、 Companys Standard Requirements For Production Materials (WSS-M99P1111-A). 3.2 CHEMICAL COMPOSITION (weight %) (ASTM A 751/ASTM E 1019) Total Carbon .7 - 1.1 Tungsten 2.0 - 4.0 Molybdenum 2.0 - 3.0 Vanadium 1.0 - 2.0 Chromium 1.0 - 2.5 Copper 11.0-21.0 Others, max 2.0 Iron Remainder Specific composi
5、tion limits, composition determination procedures, and processing route to meet performance and manufacturing requirements will form part of an agreed control plan for each component. 3.3 DENSITY, min 7.5 - 8.2 g/cm3 (ISO 2738/ASTM B 328) 3.4 APPARENT HARDNESS HRA 66 - 76 (ASTM E 18) 3.5 MICROSTRUCT
6、URE The composite microstructure shall consist of a martensitic matrix with intragranular spheroidal alloy carbides, ferritic steel regions and transition zones of pearlite and bainite. The inter-connected porosity shall be uniformly distributed throughout and be substantially filled with copper all
7、oy. Intergranular oxide film is not permitted. ENGINEERING MATERIAL SPECIFICATION WSD-M10A88-A Copyright 2012, Ford Global Technologies, Inc. Page 2 of 2 Phase identification and distribution will be controlled by reference to photomicrographs representing structures of seats for which approval is o
8、riginally given. These photomicrographs will form part of the agreed control plan. 3.6 SURFACE CONDITION Surfaces shall be free of scale and rust. Nicks, intrusions, burrs and depressions shall not exceed 0.25 mm in any direction. Visual inspection is to be performed under white light without the ai
9、d of magnification. 5. GENERAL INFORMATION The information given below is provided for clarification and assistance in meeting the requirements of this specification. 5.1 RADIAL CRUSHING STRENGTH A valve seat blank shall be loaded in a compressive manner between parallel plattens, axis of load direc
10、tion to be centrally through the test piece diameter. Load application shall be at a uniformly progressive rate avoiding any form of shock or impact loading, 2 - 10 mm/minute. The radial crushing strength shall be computed from the cross sectional area of the test piece and load to fracture. Rupture strength K = D + d P - x - D d s where D = outside diameter; d = inner diameter; P = load to breakage; s = cross section area Typical strength 1300 MPa NOTE: Attention shall be taken of test piece cross section profile, thin or irregular section may give lower values than a uniform section.
