A black heart malleable cast iron including carbon of not lower than 2.0% and not higher than 3.4%; silicon of not lower than 0% and not higher than 1.4%; aluminum of not lower than 2.0% and not higher than 6.0%, which are all expressed by percent by mass; and balance iron and inevitable impurities, wherein a value of a carbon equivalent CE expressed by Equation (1) is not lower than 3.0% and not higher than 4.2%, where C denotes a content of the carbon expressed by percent by mass, Si denotes a content of the silicon expressed by percent by mass and Al denotes a content of the aluminum expressed by percent by mass: CE=C+Si/3+Al/8 (1).

A black heart malleable cast iron including carbon of not lower than 2.0% and not higher than 3.4%; silicon of not lower than 0% and not higher than 1.4%; aluminum of not lower than 2.0% and not higher than 6.0%, which are all expressed by percent by mass; and balance iron and inevitable impurities, wherein a value of a carbon equivalent CE expressed by Equation (1) is not lower than 3.0% and not higher than 4.2%, where C denotes a content of the carbon expressed by percent by mass, Si denotes a content of the silicon expressed by percent by mass and Al denotes a content of the aluminum expressed by percent by mass: CE=C+Si/3+Al/8 (1).

The present invention relates to a high speed steel with a chemical composition that comprises, in % by weight: 0.6-2.1 C 3-5 Cr 4-14 Mo max 5 W max 15 Co 0.5-4 V, balance Fe and impurities from the manufacturing of the material, which steel is powder metallurgically manufactured and has a content of Si in the range of 0.7<Si2.

The present invention relates to a high speed steel with a chemical composition that comprises, in % by weight: 0.6-2.1 C 3-5 Cr 4-14 Mo max 5 W max 15 Co 0.5-4 V, balance Fe and impurities from the manufacturing of the material, which steel is powder metallurgically manufactured and has a content of Si in the range of 0.7<Si2.

An inoculant for the manufacture of cast iron with spheroidal graphite is disclosed, the inoculant has a particulate ferrosilicon alloy having

between 40 and 80% by weight of Si;
0.02-8% by weight of Ca;
0-5% by weight of Sr;
0-12% by weight of Ba;
0-15% by weight of rare earth metal;
0-5% by weight of Mg;
0.05-5% by weight of Al;
0-10% by weight of Mn;
0-10% by weight of Ti;
0-10 by weight of Zr;
the balance being Fe and incidental impurities in the ordinary amount,
wherein the inoculant additionally contains, by weight, based on the total weight of inoculant: 0.1 to 15% of particulate Sb.sub.2S.sub.3, and optionally between 0.1 and 15% of particulate Bi.sub.2O.sub.3, and/or between 0.1 and 15% of particulate Sb.sub.2O.sub.3, and/or between 0.1 and 15% of particulate Bi.sub.2S.sub.3, and/or between 0.1 and 5% of one or more of particulate Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, FeO, or a mixture thereof, and/or between 0.1 and 5% of one or more of particulate FeS, FeS.sub.2, Fe.sub.3S.sub.4, or a mixture thereof, a method for producing such inoculant and use of such inoculant.

An inoculant for the manufacture of cast iron with spheroidal graphite is disclosed, the inoculant has a particulate ferrosilicon alloy having

between 40 and 80% by weight of Si;
0.02-8% by weight of Ca;
0-5% by weight of Sr;
0-12% by weight of Ba;
0-15% by weight of rare earth metal;
0-5% by weight of Mg;
0.05-5% by weight of Al;
0-10% by weight of Mn;
0-10% by weight of Ti;
0-10 by weight of Zr;
the balance being Fe and incidental impurities in the ordinary amount,
wherein the inoculant additionally contains, by weight, based on the total weight of inoculant: 0.1 to 15% of particulate Sb.sub.2S.sub.3, and optionally between 0.1 and 15% of particulate Bi.sub.2O.sub.3, and/or between 0.1 and 15% of particulate Sb.sub.2O.sub.3, and/or between 0.1 and 15% of particulate Bi.sub.2S.sub.3, and/or between 0.1 and 5% of one or more of particulate Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, FeO, or a mixture thereof, and/or between 0.1 and 5% of one or more of particulate FeS, FeS.sub.2, Fe.sub.3S.sub.4, or a mixture thereof, a method for producing such inoculant and use of such inoculant.

A composite casting special-shaped roll is compounded of two parts: an inner layer and an outer layer. The shape of body of the roll is curved surface, and a center hole is arranged for mount the shaft in that central axis of roll. The casting mold is designed into two parts, namely inner cast mold and outer cast mold through the curved surface design and mold design of the roll body. The composite casting special-shaped roll with the wear-proof working layer of the roll body that is resistant to impact, rapid cooling and heating resistance and the high-strength and high-toughness core is prepared by separate casting. It meets the requirements of the service conditions of rolls used by the steel pipe and cold forming sectional steel rolling mill and other equipment, improves the service life of the roll, saves the alloy material and reduces the manufacturing cost.

A composite casting special-shaped roll is compounded of two parts: an inner layer and an outer layer. The shape of body of the roll is curved surface, and a center hole is arranged for mount the shaft in that central axis of roll. The casting mold is designed into two parts, namely inner cast mold and outer cast mold through the curved surface design and mold design of the roll body. The composite casting special-shaped roll with the wear-proof working layer of the roll body that is resistant to impact, rapid cooling and heating resistance and the high-strength and high-toughness core is prepared by separate casting. It meets the requirements of the service conditions of rolls used by the steel pipe and cold forming sectional steel rolling mill and other equipment, improves the service life of the roll, saves the alloy material and reduces the manufacturing cost.

Austempered steel for components requiring high strength and high ductility and/or fracture toughness, which has a silicon content of 3.1 weight-% to 4.4 weight-% and a carbon content of 0.4 weight-% to 0.6 weight-%. The microstructure of the austempered steel is ausferritic or superbainitic.

Austempered steel for components requiring high strength and high ductility and/or fracture toughness, which has a silicon content of 3.1 weight-% to 4.4 weight-% and a carbon content of 0.4 weight-% to 0.6 weight-%. The microstructure of the austempered steel is ausferritic or superbainitic.