A cast iron having high strength, hardness, and thermal conductivity for a cylinder liner of an internal combustion engine is provided. The cast iron includes 3.2 wt. % to 3.8 wt. % carbon, 2.2 wt. % to 3.2 wt. % silicon, 0.5 wt. % to 1.3 wt. % copper, and at least 75.0 wt. % iron, based on the total weight of the cast iron. The cast iron further includes 0.01 wt. % to 0.5 wt. % manganese, 0.01 wt. % to 0.2 wt. % chromium, up to 0.3 wt. % phosphorous, up to 0.05 wt. % sulfur, up to 0.2 wt. % tin, and up to 0.1 wt. % magnesium, based on the total weight of the cast iron. Preferably, the cast iron is free of molybdenum, nickel, and vanadium. The cast iron is also heat treated and solidifies to achieve fully spheroidal graphite.

A cast iron having high strength, hardness, and thermal conductivity for a cylinder liner of an internal combustion engine is provided. The cast iron includes 3.2 wt. % to 3.8 wt. % carbon, 2.2 wt. % to 3.2 wt. % silicon, 0.5 wt. % to 1.3 wt. % copper, and at least 75.0 wt. % iron, based on the total weight of the cast iron. The cast iron further includes 0.01 wt. % to 0.5 wt. % manganese, 0.01 wt. % to 0.2 wt. % chromium, up to 0.3 wt. % phosphorous, up to 0.05 wt. % sulfur, up to 0.2 wt. % tin, and up to 0.1 wt. % magnesium, based on the total weight of the cast iron. Preferably, the cast iron is free of molybdenum, nickel, and vanadium. The cast iron is also heat treated and solidifies to achieve fully spheroidal graphite.

A centrifugal cast caliber roll for a hot rolling mill has excellent abrasion resistance, fatigue resistance, and slip resistance. The roll has a chemical composition containing, by mass %, C: 1.8% or more and 3.0% or less, Si: 0.2% or more and 1.0% or less, Mn: 0.2% or more and 1.5% or less, Cr: 5% or more and 9% or less, Mo: 4.0% or more and 7.0% or less, V: 4.0% or more and 7.0% or less, Nb: 0.5% or more and 2.0% or less, and the balance being Fe and inevitable impurities, in which the relationship 0.6(C0.24V0.13Nb)1.4 (where C, V, and Nb each denote the content (mass %) of the corresponding chemical element) is satisfied, and has a surface hardness of Hs 67 or higher and Hs 76 or lower in terms of shore hardness.

A cold work tool material has an annealed structure including carbides, and a composition including, in mass %, C: 0.80% to 2.40%, Cr: 5.0% to 15.0%, Mo and W contained alone or in combination in an amount of (Mo+W): 0.50% to 3.00%, and V: 0.10 to 1.50%, and adjusted such that the material has a martensitic structure by quenching. The material includes a cross sectional region of an annealed structure and a length of 90 m and a width of 90 m and including no carbides having a circle equivalent diameter exceeding 5.0 m. In the cross sectional region, a proportion of a number of carbides B having a circle equivalent diameter of more than 0.1 m and not more than 0.4 m to a number of carbides A having a circle equivalent diameter of exceeds 0.1 m and not more than 2.0 m is greater than 80.0%.

A roll outer layer material contains small-size carbides having a circle equivalent diameter of 3 to 30 m in a number of 500 to 2500 pieces/mm.sup.2 and large-size carbides having a circle equivalent diameter of 50 m or more in a number of 20 pieces/mm.sup.2 or less, preferably having a chemical composition containing, by mass %, C: 2.4% or more and 2.9% or less, Si: 0.2% or more and 1.0% or less, Mn: 0.2% or more and 1.0% or less, Cr: 4.0% or more and 7.5% or less, Mo: 4.0% or more and 6.5% or less, V: 5.3% or more and 7.0% or less, Nb: 0.5% or more and 3.0% or less, and the balance being Fe and inevitable impurities, in which the contents of Cr, Mo, and V satisfy the relationship 1.5(Cr+Mo)/V2.4.

A roll outer layer material contains small-size carbides having a circle equivalent diameter of 3 to 30 m in a number of 500 to 2500 pieces/mm.sup.2 and large-size carbides having a circle equivalent diameter of 50 m or more in a number of 20 pieces/mm.sup.2 or less, preferably having a chemical composition containing, by mass %, C: 2.4% or more and 2.9% or less, Si: 0.2% or more and 1.0% or less, Mn: 0.2% or more and 1.0% or less, Cr: 4.0% or more and 7.5% or less, Mo: 4.0% or more and 6.5% or less, V: 5.3% or more and 7.0% or less, Nb: 0.5% or more and 3.0% or less, and the balance being Fe and inevitable impurities, in which the contents of Cr, Mo, and V satisfy the relationship 1.5(Cr+Mo)/V2.4.

A seal ring comprising a chromium and boron containing cast iron alloy composition is disclosed. The cast iron alloy composition comprises each of boron, chromium and silicon in the following amounts: boron up to 1.5 wt. %; chromium from 8 to 14 wt. %; and silicon up to 3.0 wt. %. The seal ring may be produced by melting a cast iron composition further comprising the foregoing alloying elements; pouring the melted alloy into a mold; cooling the melted alloy to form a cast iron seal ring; and separating the cast iron seal ring from the mold. The seal ring is typically used in the undercarriage of earth-working machines, such as in the drive train or power train of such machines.

A powder metal steel alloy composition for high wear and temperature applications is made by water atomizing a molten steel alloy composition containing C in an amount of at least 3.0 wt %; at least one carbide-forming alloy element selected from the group consisting of: Cr, V, Mo or W; an O content less than about 0.5 wt %, and the balance comprising essentially Fe apart from incidental impurities. The high carbon content reduces the solubility of oxygen in the melt and thus lowers the oxygen content to a level below which would cause the carbide-forming element(s) to oxidize during water atomization. The alloy elements are thus not tied up as oxides and are available to rapidly and readily form carbides in a subsequent sintering stage. The carbon, present in excess, is also available for diffusing into one or more other admixed powders that may be added to the prealloyed powder during sintering to control microstructure and properties of the final part.

A nodular graphite cast iron, a method for fabricating a vane for a rotary compressor using nodular graphite cast iron, and a vane for a rotary compressor using the same are provided. The nodular graphite cast iron includes 3.4 wt % to 3.9 wt % of carbon (C), 2.0 wt % to 3.0 wt % of silicon (Si), 0.3 wt % to 1.0 wt % of manganese (Mn), 0.1 wt % to 1.0 wt % of chromium (Cr), 0.04 wt % to 0.15 wt % of titanium (Ti), less than 0.08 w % of phosphorus (P), less than 0.025 wt % of sulphur (S), 0.03 wt % to 0.05 wt % of magnesium (Mg), 0.02 wt % to 0.04 wt % of rare earth resource, iron (Fe) and impurities as the remnants, and includes a bainite matrix structure, nodular graphite, and 15 vol % to 35 vol % of carbide.

A nodular graphite cast iron, a method for fabricating a vane for a rotary compressor using nodular graphite cast iron, and a vane for a rotary compressor using the same are provided. The nodular graphite cast iron includes 3.4 wt % to 3.9 wt % of carbon (C), 2.0 wt % to 3.0 wt % of silicon (Si), 0.3 wt % to 1.0 wt % of manganese (Mn), 0.1 wt % to 1.0 wt % of chromium (Cr), 0.04 wt % to 0.15 wt % of titanium (Ti), less than 0.08 w % of phosphorus (P), less than 0.025 wt % of sulphur (S), 0.03 wt % to 0.05 wt % of magnesium (Mg), 0.02 wt % to 0.04 wt % of rare earth resource, iron (Fe) and impurities as the remnants, and includes a bainite matrix structure, nodular graphite, and 15 vol % to 35 vol % of carbide.