Abstract: A cemented carbide comprising 55-90 parts by mass of WC particles and 10-45 parts by mass of a Fe-based binder phase; the binder phase having a composition comprising 0.5-10% by mass of Ni, 0.2-2% by mass of C, 0.5-5% by mass of Cr, 0.2-2.0% by mass of Si, and 0.1-5% by mass of W, the balance being Fe and inevitable impurities, and containing 0.05-2.0% by area of Fe—Si—O-based particles.

Abstract: A composite cemented carbide roll comprising an inner layer made of an iron-based alloy, and an outer layer made of cemented carbide which is metallurgically bonded to an outer peripheral surface of the inner layer; the cemented carbide of the outer layer comprising 55-90 parts by mass of WC particles and 10-45 parts by mass of an Fe-based binder phase having a particular composition; a shaft member and a shaft end member being metallurgically bonded to at least one axial end of the inner layer; the inner layer being made of an iron-based alloy containing 2.0% or more in total by mass of at least one selected from the group consisting of Cr, Ni and Mo; and the shaft member and the shaft end member being made of an iron-based alloy containing 1.5% or less in total by mass of at least one selected from the group consisting of Cr, Ni and Mo.

Abstract: A composite cemented carbide roll comprising an inner layer made of an iron-based alloy, and an outer layer made of cemented carbide which is metallurgically bonded to an outer peripheral surface of the inner layer; the cemented carbide of the outer layer comprising 55-90 parts by mass of WC particles and 10-45 parts by mass of an Fe-based binder phase having a particular composition; a shaft member and a shaft end member being metallurgically bonded to at least one axial end of the inner layer; the inner layer being made of an iron-based alloy containing 2.0% or more in total by mass of at least one selected from the group consisting of Cr, Ni and Mo; and the shaft member and the shaft end member being made of an iron-based alloy containing 1.5% or less in total by mass of at least one selected from the group consisting of Cr, Ni and Mo.

Abstract: A composite cemented carbide roll comprising an inner layer made of steel, and intermediate and outer layers made of cemented carbide containing WC particles; the cemented carbide forming the outer layer comprising 55-90 parts by mass of WC particles, and 10-45 parts by mass of a binder phase having a particular composition comprising Fe as a main component; the cemented carbide forming the intermediate layer comprising 30-65 parts by mass of WC particles, and 35-70 parts by mass of a binder phase having a particular composition comprising Fe as a main component; and the amount c1 (parts by mass) of WC particles in the outer layer and the amount c2 (parts by mass) of WC particles in the intermediate layer meeting 0.45?c2/c1?0.85.

Abstract: A cemented carbide comprising 55-90 parts by mass of WC particles and 10-45 parts by mass of a Fe-based binder phase; the binder phase having a composition comprising 0.5-10% by mass of Ni, 0.2-2% by mass of C, 0.5-5% by mass of Cr, 0.2-2.0% by mass of Si, and 0.1-5% by mass of W, the balance being Fe and inevitable impurities, and containing 0.05-2.0% by area of Fe—Si—O-based particles.

Abstract: A composite cemented carbide roll comprising an inner layer made of steel, and intermediate and outer layers made of cemented carbide containing WC particles; the cemented carbide forming the outer layer comprising 55-90 parts by mass of WC particles, and 10-45 parts by mass of a binder phase having a particular composition comprising Fe as a main component; the cemented carbide forming the intermediate layer comprising 30-65 parts by mass of WC particles, and 35-70 parts by mass of a binder phase having a particular composition comprising Fe as a main component; and the amount c1 (parts by mass) of WC particles in the outer layer and the amount c2 (parts by mass) of WC particles in the intermediate layer meeting 0.45?c2/c1?0.85.

Abstract: A cemented carbide comprising 55-90 parts by mass of WC particles, and 10-45 parts by mass of an Fe-based binder phase, the binder phase having a composition comprising 2.5-10% by mass of Ni, 0.2-1.2% by mass of C, 0.5-5% by mass of Cr, 0.2-2.0% by mass of Si, 0.1-3% by mass of W, 0-5% by mass of Co, and 0-1% by mass of Mn, the balance being substantially Fe and inevitable impurities, and the cemented carbide being substantially free from composite carbides having major axes of 5 ?m or more. This cemented carbide is produced by cooling at a cooling rate of 60° C./hour or more between 900° C. and 600° C., after vacuum sintering.

Abstract: A cemented carbide comprising 55-90 parts by mass of WC particles, and 10-45 parts by mass of an Fe-based binder phase, the binder phase having a composition comprising 2.5-10% by mass of Ni, 0.2-1.2% by mass of C, 0.5-5% by mass of Cr, 0.2-2.0% by mass of Si, 0.1-3% by mass of W, 0-5% by mass of Co, and 0-1% by mass of Mn, the balance being substantially Fe and inevitable impurities, and the cemented carbide being substantially free from composite carbides having major axes of 5 ?m or more. This cemented carbide is produced by cooling at a cooling rate of 60° C./hour or more between 900° C. and 600° C., after vacuum sintering.

Abstract: A centrifugally cast composite roll for hot rolling comprising an outer layer having a composition comprising by mass 0.8-3.5% of C, 0.1-2.5% of Si, 0.1-2.5% of Mn, 1.2-15% of Cr, 1-5% of Ni, and 1-10% of Mo+0.5×W, the balance being substantially Fe and inevitable impurities, and an inner layer made of an iron-based alloy and integrally fused to the outer layer; the outer layer having Shore hardness of 67-82 at the initial diameter of the composite roll; and the maximum Shore hardness of the outer layer in a range 30 mm or more deep from the initial diameter being higher by 1 or more than the Shore hardness of the outer layer at the initial diameter.

Abstract: A centrifugally cast composite roll for hot rolling comprising an outer layer having a composition comprising by mass 0.8-3.5% of C, 0.1-2.5% of Si, 0.1-2.5% of Mn, 1.2-15% of Cr, 1-5% of Ni, and 1-10% of Mo+0.5×W, the balance being substantially Fe and inevitable impurities, and an inner layer made of an iron-based alloy and integrally fused to the outer layer; the outer layer having Shore hardness of 67-82 at the initial diameter of the composite roll; and the maximum Shore hardness of the outer layer in a range 30 mm or more deep from the initial diameter being higher by 1 or more than the Shore hardness of the outer layer at the initial diameter.

Abstract: A wear-resistant compound roll comprising an outer layer made of an iron-base alloy containing such components as to precipitate at least one of carbides of W, V, Nb, Ti, Ta, Zr and Hf from an alloy melt in a solidification process thereof, and a steel shaft metallurgically bonded to the outer layer, the outer layer having a surface with a Shore hardness of 70 or more, and the shaft having a tensile strength of 55 kg/mm.sup.2 or more and an elongation of 1.0% or more, and a boundary layer between the outer layer and the shaft being not weaker than weaker one of the outer layer and the shaft.The iron-base alloy has a composition by weight % consisting essentially of 1.5-3.5% C, 0.3-3.0% Si, 0.3-1.5% Mn, 2-7% Cr, 9% or less Mo, 20% or less W, 3-15% V and balance substantially Fe.