Abstract: A computer implemented method for training a neural network to capture a structural feature specific to a set of chemical compounds is disclosed. In the method, the computer system reads an expression describing a structure of the chemical compound for each chemical compound in the set and enumerates one or more combinations of a position and a type of a structural element appearing in the expression for each chemical compound in the set. The computer system also generates training data based on the one or more enumerated combinations for each chemical compound in the set. The training data includes one or more values with a length, each of which indicates whether or not a corresponding type of the structural element appears at a corresponding position for each combination. Furthermore, the computer system trains the neural network based on the training data for the set of the chemical compounds.

Abstract: The invention provides a hard-particle powder for sintered body, which contains, by mass %, 2% to 3.5% of Si, 6% to 10% of Cr, 20% to 35% of Mo, 0.01% to 0.5% of REM, and the remainder being Co and unavoidable impurities. The invention further provides a sintered body obtained through a mixing step of mixing the above-mentioned hard-particle powder for sintered body with a pure iron powder and a graphite powder to obtain a powder mixture, a forming step of compacting the powder mixture to obtain a compact, and a sintering step of sintering the compact. The hard-particle powder according to the invention has the effect of giving a sintered body having improved wear resistance without substantially impairing powder characteristics and sintering characteristics. Additionally, the sintered body according to the invention has the effect of having excellent wear resistance.

Abstract: The invention provides a hard-particle powder for sintered body, which contains, by mass %, 2% to 3.5% of Si, 6% to 10% of Cr, 20% to 35% of Mo, 0.01% to 0.5% of REM, and the remainder being Co and unavoidable impurities. The invention further provides a sintered body obtained through a mixing step of mixing the above-mentioned hard-particle powder for sintered body with a pure iron powder and a graphite powder to obtain a powder mixture, a forming step of compacting the powder mixture to obtain a compact, and a sintering step of sintering the compact. The hard-particle powder according to the invention has the effect of giving a sintered body having improved wear resistance without substantially impairing powder characteristics and sintering characteristics. Additionally, the sintered body according to the invention has the effect of having excellent wear resistance.

Abstract: The present invention provides a Ni-based super alloy including, by mass %, C: 0.01 to 0.15%; Si: 1% or less; Mn: 1% or less; P: 0.02% or less; S: 0.01% or less; Co: less than 0.10%; Cr: 16 to 22%; Mo: 4 to 10%; W: 5% or less; Al: 1.2 to 2.5%; Ti: 2.4 to 4%; B: 0.001 to 0.05%; Zr: 0.01 to 0.5%; Fe: 1% or less; and a balance of Ni and inevitable impurities.

Abstract: A hot work tool steel having a chemical composition in wt %: C: 0.10 to 0.35%, Si: less than 0.80%, Mn: 3.0% or less, Cr: 2.0% or more and less than 7.0%, N: more than 0.05% and 0.50% or less, O: 0.0100% or less, P: 0.050% or less, Al: 0.050% or less, with the proviso that ½W+Mo: 0.3 to 5.0%, C+N: 0.20 to 0.60% and C/N: 6 or less, and the balance: substantially Fe, and optionally V: 0.01 to 0.5%. The hot work tool steel exhibits excellent resistance to melting, while retaining good toughness and good resistance to heat checking.

Abstract: An exhaust valve for automobile engines, which is durable at such a high temperature as 900° C., and exhibits high fatigue strength and high oxidation resistance is disclosed. The exhaust valve is made of a Ni-based alloy consisting essentially of, by weight %. C: 0.01-0.15%, Si: up to 2.0%, Mn: up to 1.0%, P: up to 0.02%, S: up to 0.01%, Co: 0.1-15%, Cr: 15-25%, one or two of Mo: 0.1-10% and W: 0.1-5% in such amount that Mo+½ W; 3-10%, Al: 1.0-3.0%, Ti: 2.0-3.5%, provided that, by atomic %, Al+Ti: 6.3-8.5% and Ti/Al ratio: 0.4-0.8, and further, by weight %, B: 0.001-0.01%, Fe: up to 3%, and the balance of Ni and inevitable impurities by hot forging to give the form of an exhaust valve and subjecting to solid solution at 1000-1200° C. and aging at 700-950° C.

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.