1、 ENGINEERING MATERIAL SPECIFICATIONDate Action Revisions 2004 12 21 Activated R. Thomas, T. Covert Printed copies are uncontrolled Copyright 2004, Ford Global Technologies, LLC Page 1 of 4 GRAY IRON, BRAKE COMPONENTS, DRUMS AND ROTORS, WSS-M1A176-B2 CLASS 30 GRAY IRON, BRAKE COMPONENTS, DRUMS AND RO
2、TORS, WSS-M1A176-B3 LOW STRENGTH, HIGH CARBON EQUIVALENT 1. SCOPE The materials defined in these specifications are low to medium strength structural gray cast iron. 2. APPLICATION B2 is a class 30 gray iron and may be used for all brake rotor and brake drum applications. B3 is a lower-strength, hig
3、h carbon equivalent grade and shall not be used for unicast rotor applications. 3. REQUIREMENTS 3.1 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material suppliers and part producers must conform to the Companys Standard Requirements For Production Materials (WSS-M99P1111-A). 3.2 PART SAMPLING LOC
4、ATIONS Cast or finished components must be used to determine conformance to this specification unless otherwise indicated on Engineering Drawing. Table Part Sampling Locations * Fig. 1 Tensile Test Bar Hardness Microstructure Full-cast (or loose) Brake Rotor * Center of brake plate Center of brake p
5、late Center of brake plate Unicast Brake Rotor* Wheel mounting flange Center of brake plate Cross-section of cup seat otherwise there will be a bimodal distribution for tensile strength and hardness with unacceptable microstructural variation affecting machining and customer. Casting source should u
6、se a process with the minimal alloy content necessary to meet requirements and reduce material property variation. 4.1.2 Control of Microstructure Ferrosilicon inoculants and/or graphitizing agents should be added to the molten iron or in the mold to reduce chilling tendency and reduce variation in
7、the resultant microstructure. Use of thermal analysis is strongly recommended. 4.1.3 Chemical Composition (wt. Percent) (ASTM E 415) Since processes may vary by supplier, the following chemical composition is shown only as a guideline. B2 B3 Carbon Equivalent 4.30 Max. 4.30 4.80 Manganese 0.50 0.70
8、0.50 0.70 Sulfur 0.15 Max. 0.15 Max. Total Carbon 3.40 - 3.65 3.60 3.90 Silicon 1.60 - 2.40 2.10 2.90 Phosphorus 0.12 Max. 0.12 Max. Chromium 0.40 Max. 0.25 Max. Copper - 0.25 Max. Carbon Equivalent = % Total Carbon + 1/3 % Silicon - 1/3 (% Chromium - 0.10). ENGINEERING MATERIAL SPECIFICATIONWSS-M1A176-B2/B3 Printed copies are uncontrolled Copyright 2004, Ford Global Technologies, LLC Page 4 of 4 Figure 1
