Spheroidal graphite cast iron alloy containing carbon, silicon and molybdenum and disc brake rotor thereof

摘要

A spheroidal graphite cast iron alloy consisting essentially of, by weight 1.5 to 4.5% carbon, 1.5 to 4.5% silicon, 1.2 to 6.5% molybdenum, optionally nickel and/or copper, where the (% molybdenum + % nickel + % copper) does not exceed 6.5%, balance iron and incidental impurities. The alloy has a microstructure which comprises very soft nodules of graphite surrounded by relatively soft and ductile ferrite, the soft nodules of graphite being strengthened and hardened by a pearlite phase of the alloy and/or strengthened and hardened by a very hard complex carbide phase. Also described is a spheroidal graphite cast iron alloy that consists essentially of, by weight 3 to 3.35% carbon, 1.9 to 2.58% silicon and 3.0% molybdenum, balance iron and incidental impurities. Also described is a disc brake rotor manufactured wholly or partly from either of the alloys described above.