Abstract: The present invention relates to a negative electrode active material including an Si—Sn—Fe—Cu based alloy, in which an Si phase has an area ratio in a range of from 35 to 80% in the entire negative electrode active material, the Si phase is dispersed in a matrix phase, the matrix phase contains an Si—Fe compound phase crystallized around the Si phase and further contains an Sn—Cu compound phase crystallized to surround the Si phase and the Si—Fe compound phase, the Si—Fe compound phase is crystallized in a ratio of from 35 to 90% in terms of an area ratio in the entire matrix phase, and the matrix phase further contains an Sn phase unavoidably crystallized in the matrix phase in a ratio of 15% or less in terms of an area ratio in the entire matrix phase.

Abstract: The present invention relates to a negative electrode active material including an Si—Sn—Fe—Cu based alloy, in which an Si phase has an area ratio in a range of from 35 to 80% in the entire negative electrode active material, the Si phase is dispersed in a matrix phase, the matrix phase contains an Si—Fe compound phase crystallized around the Si phase and further contains an Sn—Cu compound phase crystallized to surround the Si phase and the Si—Fe compound phase, the Si—Fe compound phase is crystallized in a ratio of from 35 to 90% in terms of an area ratio in the entire matrix phase, and the matrix phase further contains an Sn phase unavoidably crystallized in the matrix phase in a ratio of 15% or less in terms of an area ratio in the entire matrix phase,

Abstract: The present invention provides a two-way shape-recovery alloy, which contains less than 0.20 mass % of C, 13.00 to 30.00 mass % of Mn, 0.10 to 6.00 mass % of Si, 0.05 to 12.00 mass % of Cr, 0.01 to 3.00 mass % of Ni, and less than 0.100 mass % of N, with the remainder being Fe and unavoidable impurities, in which the contents of Mn, Si, Cr and Ni satisfy the following expression (1): 600?33Mn+11Si+28Cr+17Ni?1050??(1).

Abstract: Disclosed is an improved low alloy high speed tool steel, which exhibits constant toughness with small dispersion of the properties after heat treatment and regardless of the size of the products. The steel consists essentially of, by weight %, C: 0.50-0.75%, Si: 0.02-2.00%, Mn: 0.1-3.0%, P: up to 0.050%, S: up to 0.010%, Cr: 5.0-6.0%, W: 0.5-2.0%, V: 0.70-1.25%, Al: up to 0.1%, O: up to 0.01% and N: up to 0.04% and the balance of Fe. In the steel [Mo+0.5W](Mo-eq.) is 2.5-5.0%, [Mo-eq.]/V is 2-4. In the annealed state the steel contains carbides of the types of MC+M6C and/or M23C6(M7C3), and after quenching from a temperature of 1100-1200° C. it contains substantially no remaining carbide or, even contains, almost all the carbides are of MC.

Abstract: To provide an alloy tool steel having high-temperature strength at an operating temperature of the order of 700° C., while maintaining room-temperature strength as high as that of a conventional matrix high-speed tool steel. The steel contains from 0.45 wt % to 0.65 wt % C, from 0.10 wt % to 1.00 wt % Si, from 0.20 wt % to 2.00 wt % Mn, not more than 0.020 wt % P, not more than 0.015 wt % S, not more than 1.00 wt % Cu, not more than 1.00 wt % Ni, from 3.50 wt % to 5.00 wt % Cr, from 0.00 wt % to 3.00 wt % Mo, from 0.00 wt % to 10.00 wt % W, from 1.00 wt % to 2.00 wt % V, from 0.00 wt % to 8.00 wt % Co, not more than 0.10 wt % Al, not more than 0.01 wt % O, not more than 0.02 wt % N, and the balance substantially constituted of Fe and unavoidable impurities, in which Weq is from 2.0 to 10.0, 2Mo/Weq is not more than 0.60, and ?C is from ?0.3 to 0.0.

Abstract: Disclosed is an improved low alloy high speed tool steel, which exhibits constant toughness with small dispersion of the properties after heat treatment and regardless of the size of the products. The steel consists essentially of, by weight %, C: 0.50-0.75%, Si: 0.02-2.00%, Mn: 0.1-3.0%, P: up to 0.050%, S: up to 0.010%, Cr: 5.0-6.0%, W: 0.5-2.0%, V: 0.70-1.25%, Al: up to 0.1%, O: up to 0.01% and N: up to 0.04% and the balance of Fe. In the steel [Mo+0.5W](Mo-eq.) is 2.5-5.0%, [Mo-eq.]/V is 2-4. In the annealed state the steel contains carbides of the types of MC+M6C and/or M23C6(M7C3), and after quenching from a temperature of 1100-1200° C. it contains substantially no remaining carbide or. even contains, almost all the carbides are of MC.

Abstract: To provide an alloy tool steel having high-temperature strength at an operating temperature of the order of 700° C., while maintaining room-temperature strength as high as that of a conventional matrix high-speed tool steel. The steel contains from 0.45 wt % to 0.65 wt % C, from 0.10 wt % to 1.00 wt % Si, from 0.20 wt % to 2.00 wt % Mn, not more than 0.020 wt % P, not more than 0.015 wt % S, not more than 1.00 wt % Cu, not more than 1.00 wt % Ni, from 3.50 wt % to 5.00 wt % Cr, from 0.00 wt % to 3.00 wt % Mo, from 0.00 wt % to 10.00 wt % W, from 1.00 wt % to 2.00 wt % V, from 0.00 wt % to 8.00 wt % Co, not more than 0.10 wt % Al, not more than 0.01 wt % O, not more than 0.02 wt % N, and the balance substantially constituted of Fe and unavoidable impurities, in which Weq is from 2.0 to 10.0, 2Mo/Weq is not more than 0.60, and ?C is from ?0.3 to 0.0.

Abstract: Disclosed is an improved low alloy high speed tool steel, which exhibits constant toughness with small dispersion of the properties after heat treatment and regardless of the size of the products. The steel consists essentially of, by weight %, C: 0.50-0.75%, Si: 0.02-2.00%, Mn: 0.1-3.0%, P: up to 0.050%, S: up to 0.010%, Cr: 5.0-6.0%, W: 0.5-2.0%, V: 0.70-1.25%, Al: up to 0.1%, 0: up to 0.01% and N: up to 0.04% and the balance of Fe. In the steel [Mo+0.5W](Mo-eq.) is 2.5-5.0%, [Mo-eq.]/V is 2-4. In the annealed state the steel contains carbides of [MC+M6C]-type and/or M23C6(M7C3)-type, and after quenching from a temperature of 1100-1200° C., it contains substantially no remainig carbide or, even contains, almost all the carbides are of MC-type.

Abstract: A free-cutting tool steel is provided containing Fe and C in an amount of 0.1 to 2.5 wt %, Ti and or Zr where WTi+0.52WZr constitutes 0.03 to 3.5 wt %, and WTi represents Ti content and WZr represents Zr content, at least any one of S, Se and Te where WS+0.4WSe+0.25WTe constitutes 0.01 to 1.0 wt %, and (WTi+0.52WZr)/(WS+0.4WSe+0.25WTe) constitutes 1 to 4, and WS represents S content, WSe represents Se content and WTe represents Te content; and dispersed therein a texture thereof from 0.1 to 10% in terms of area ratio in a section of a machinability improving compound phase of a metallic element component of Ti and/or Zr as major components, and a binding component for the metallic element component containing C and any one of S, Se and Te.

Abstract: A free-cutting tool steel is provided containing Fe and C in an amount of 0.1 to 2.5 wt %, Ti and or Zr where WTi+0.52WZr constitutes 0.03 to 3.5 wt %, and WTi represents Ti content and WZr represents Zr content, at least any one of S, Se and Te where WS+0.4WSe+0.25WTe constitutes 0.01 to 1.0 wt %, and (WTi+0.52WZr)/(WS+0.4WSe+0.25WTe) constitutes 1 to 4, and WS represents S content, WSe represents Se content and WTe represents Te content; and dispersed therein a texture thereof from 0.1 to 10% in terms of area ratio in a section of a machinability improving compound phase of a metallic element component of Ti and/or Zr as major components, and a binding component for the metallic element component containing C and any one of S, Se and Te.

Abstract: A cast cold tool is obtained through the steps of forming a casting by founding a molten steel consisting by weight percentage of 0.5 to 0.8% of C, not more than 1.0% of Si, 0.25 to 1.50% of Mn, 4.0 to 8.0% of Cr, 1.0 to 5.0% of Mo, one or both of 0.2 to 1.0% of V and 0.2 to 2.0% of Nb, opptionally not more than 2.5% of W, not more than 2.5% of Ni, and the balance being Fe plus incidental impurities, subjecting the casting to solid solution treatment to decrease primary carbides precipitated in the casting to not more than 1%, preferably to extinguish completely, and subjecting the solid-solution treated casting to quenching and tempering treatment to give predetermined toughness and hardness to the casting.

Abstract: A high Young's modulus material comprises carbon steel or alloying steel and contains a particular amount of hard particles having a Young's modulus of not less than 24,000 kgf/mm.sup.2. Furthermore, a surface-coated tool member comprises a substrate comprised of carbon steel or alloying steel and a hard coating layer having a Young's modulus of not less than 24,000 kgf/mm.sup.2 in which the substrate contains a particular amount of hard particles having a Young's modulus of not less than 24,000 kgf/mm.sup.2.