An iron-based alloy includes, in weight percent, carbon from about 2 to about 3 percent; manganese from about 0.1 to about 0.4 percent; silicon from about 0.3 to about 0.8 percent; chromium from about 11.5 to about 14.5 percent; nickel from about 0.05 to about 0.6 percent; vanadium from about 0.8 to about 2.2 percent; molybdenum from about 4 to about 7 percent; tungsten from about 3 to about 5 percent; niobium from about 1 to about 3 percent; cobalt from about 3 to about 5 percent; boron from zero to about 0.2 percent; and the balance containing iron and incidental impurities. The alloy is suitable for use in elevated temperature applications such as in valve seat inserts for combustion engines.

A nodular cast alloy, a casting made therefrom, and a production process therefor, which has a perlitic-ferritic microstructure for cast iron products and has a high strength combined with good ductility and toughness even in the cast state, including, as nonferrous constituents, C, Si, Ni, Mn, Cu, Mg, Cr, Al, P, S and normal impurities, characterized in that the nodular cast alloy in the cast state without subsequent heat treatment achieves a high static strength of a 0.2% offset yield strength of 600 MPa and a tensile strength of 750 MPa combined with good ductility of an elongation at break A5 of from 2 to 10%.

A high-strength, high-damping-capacity cast iron having both a high strength and high vibration damping capacity is provided. The high-strength, high-damping-capacity cast iron is obtained by a method including performing a graphite spheroidizing treatment on a molten metal, and consists of 2% to 4% of C, 1% to 5% of Si, 0.2% to 0.9% of Mn, 0.1% or less of P, 0.1% or less of S, 3% to 7% of Al, 0% to 1% of Sb, 0% to 0.5% of Sn, 0.02% to 0.10% of Mg, 01% to 0.5% of RE (Ce, La), Fe as balance, and unavoidable impurity.

A high-strength, high-damping-capacity cast iron having both a high strength and high vibration damping capacity is provided. The high-strength, high-damping-capacity cast iron is obtained by a method including performing a graphite spheroidizing treatment on a molten metal, and consists of 2% to 4% of C, 1% to 5% of Si, 0.2% to 0.9% of Mn, 0.1% or less of P, 0.1% or less of S, 3% to 7% of Al, 0% to 1% of Sb, 0% to 0.5% of Sn, 0.02% to 0.10% of Mg, 01% to 0.5% of RE (Ce, La), Fe as balance, and unavoidable impurity.

A method for forming an austempered iron composition with a nanoscale microstructure includes a step of heating an iron-carbon-silicon alloy with silicon to a first temperature that is lower than A1 for the iron-carbon-silicon alloy. The iron-carbon-silicon alloy is then adiabatically deformed such that the temperature of the iron-carbon-silicon alloy rises to a second temperature which is sufficient to form proeutectoid ferrite and austenite. The iron-carbon-silicon alloy is cooled to a first austempering temperature. The iron-carbon-silicon alloy is then heated to a second austempering temperature that is greater than the first austempering temperature to form a dual phase microstructure. Characteristically, the dual phase microstructure includes proeutectoid ferrite and ausferrite.

A method for forming an austempered iron composition with a nanoscale microstructure includes a step of heating an iron-carbon-silicon alloy with silicon to a first temperature that is lower than A1 for the iron-carbon-silicon alloy. The iron-carbon-silicon alloy is then adiabatically deformed such that the temperature of the iron-carbon-silicon alloy rises to a second temperature which is sufficient to form proeutectoid ferrite and austenite. The iron-carbon-silicon alloy is cooled to a first austempering temperature. The iron-carbon-silicon alloy is then heated to a second austempering temperature that is greater than the first austempering temperature to form a dual phase microstructure. Characteristically, the dual phase microstructure includes proeutectoid ferrite and ausferrite.

A scroll compressor includes scroll members that are made of austempered grey iron in whole or in part. The austempering process can increases fatigue strength and toughness of a grey iron while maintaining its good machinability and vibration damping characteristics. Use of austempered grey iron scroll members allows the scroll compressor to improve its capacity, efficiency, and durability.

A scroll compressor includes scroll members that are made of austempered grey iron in whole or in part. The austempering process can increases fatigue strength and toughness of a grey iron while maintaining its good machinability and vibration damping characteristics. Use of austempered grey iron scroll members allows the scroll compressor to improve its capacity, efficiency, and durability.

The present invention relates to an alloy cast iron, and a piston ring containing the same, the alloy cast iron including: a pearlite matrix; and a graphite structure and a steadite-type eutectic structure which are precipitated in the pearlite matrix, wherein the steadite-type eutectic structure includes at least one element selected from boron (B) and vanadium (V), at least one element selected from chromium (Cr) and molybdenum (Mo), and copper (Cu).

The present invention relates to an alloy cast iron, and a piston ring containing the same, the alloy cast iron including: a pearlite matrix; and a graphite structure and a steadite-type eutectic structure which are precipitated in the pearlite matrix, wherein the steadite-type eutectic structure includes at least one element selected from boron (B) and vanadium (V), at least one element selected from chromium (Cr) and molybdenum (Mo), and copper (Cu).