Abstract: Provided is austenitic heat-resisting cast steel that is excellent in both of the heat resistance and the machinability. Austenitic heat-resisting cast steel, includes: C: 0.1 to 0.4 mass %; Si: 0.8 to 2.5 mass %; Mn: 0.8 to 2.0 mass %; S: 0.05 to 0.30 mass %; Ni: 5 to 20 mass %; N: 0.3 mass % or less; Zr: 0.01 to 0.20 mass %; Ce: 0.01 to 0.10 mass %; one type or more of the elements selected from the following groups of (i) to (iii), at least including (i), (i) Cr: 14 to 24 mass %, (ii) Nb: 1.5 mass % or less, and (iii) Mo: 3.0 mass % or less; and Fe and inevitable impurity as a remainder.

Abstract: Provided is austenitic: heat-resisting cast steel that is excellent in both of the heat resistance and the machinability. Austenitic heat-resisting cast steel, includes: C: 0.1 to 0.4 mass %; Si: 0.8 to 2.5 mass %, Mn: 0.8 to 2.0 mass %: S: 0.05 to 0.30 mass %, Ni: 5 to 20 mass %; N: 0.3 mass % or less; Zr: 0.01 to 0.20 mass %; Ce: 0.01 to 0.10 mass %; one type or more of the elements selected from the following groups of (i) to (iii), at least including (i), (i) Cr: 14 to 24 mass %, (ii) Nb: 1.5 mass % or less, and Mo: 3.0 mass % or less; and Fe and inevitable impurity as a remainder.

Abstract: Provided is austenite heat-resisting cast steel with reduced precipitation of ferrite phase during the application of thermal load to stabilize the austenite structure for improved heat resistance. The austenite heat-resisting cast steel contains elements of 0.1 to 0.6 mass % of C, 1.0 to 2.5 mass % of Si, 1.0 to 3.5 mass % of Mn, 0.05 to 0.2 mass % of S, 14 to 24 mass % of Cr, 5 to 20 mass % of Ni, 0.1 to 0.3 mass % of N, 0.01 to 1.2 mass % of Zr, 0.01 to 1.5 mass % of Cu, 0.01 to 1.5 mass % of Nb, Fe as a remainder and unavoidable impurity. The elements satisfy the following expressions: Mn—S?1.0; and C?(1/12Cr?32Zr)>0, where symbols for elements in these expressions represent values indicating content of the elements corresponding to the symbols in a unit of atomic %.

Abstract: Provided is austenite heat-resisting cast steel with reduced precipitation of ferrite phase during the application of thermal load to stabilize the austenite structure for improved heat resistance. The austenite heat-resisting cast steel contains elements of 0.1 to 0.6 mass % of C, 1.0 to 2.5 mass % of Si, 1.0 to 3.5 mass % of Mn, 0.05 to 0.2 mass % of S, 14 to 24 mass % of Cr, 5 to 20 mass % of Ni, 0.1 to 0.3 mass % of N, 0.01 to 1.2 mass % of Zr, 0.01 to 1.5 mass % of Cu, 0.01 to 1.5 mass % of Nb, Fe as a remainder and unavoidable impurity. The elements satisfy the following expressions: Mn—S?1.0; and C?(1/12Cr?32Zr)>0, where symbols for elements in these expressions represent values indicating content of the elements corresponding to the symbols in a unit of atomic %.

Abstract: A piston for in-cylinder fuel-injection type internal combustion engine includes a piston body, a low thermal conductor, and a piston head. The low thermal conductor is disposed on the top of the piston body. The low thermal conductor includes a low thermally-conductive substrate, and a coating layer. The low thermally-conductive substrate has opposite surfaces. The coating layer includes alumina fine particles (Al2O3). The coating layer is adhered on at least a part one of the opposite surfaces of the low thermally-conductive substrate that makes a cast-buried or enveloped surface to be cast buried or enveloped in the piston head.

Abstract: There is provided an electron conductive and corrosion-resistant material 3 containing titanium (Ti), boron (B) and nitrogen (N) in an atomic ratio satisfying 0.05?[Ti]?0.40, 0.20?[B]?0.40, and 0.35?[N]?0.55 (provided that [Ti]+[B]+[N]=1). Further, there is provided a method of manufacturing an electron conductive and corrosion-resistant material 3, wherein boron nitride powder adheres to the surface of a substrate 2 of which at least the surface is made of titanium or a titanium alloy, and is then heated. Furthermore, there is provided a method of manufacturing an electron conductive and corrosion-resistant material 3, wherein the surface of a substrate 2 of which at least the surface is made of titanium or a titanium alloy is borided and then heated. In addition, there is provided a method of manufacturing an electron conductive and corrosion-resistant material 3, wherein a TiB2 layer formed of TiB2 particles is formed by spraying TiB2 powder onto a metal substrate 2 and then nitriding the TiB2 layer.

Abstract: A piston for in-cylinder fuel-injection type internal combustion engine includes a piston body, a low thermal conductor, and a piston head. The low thermal conductor is disposed on the top of the piston body. The low thermal conductor includes a low thermally-conductive substrate, and a coating layer. The low thermally-conductive substrate has opposite surfaces. The coating layer includes alumina fine particles (Al2O3). The coating layer is adhered on at least a part one of the opposite surfaces of the low thermally-conductive substrate that makes a cast-buried or enveloped surface to be cast buried or enveloped in the piston head.

Abstract: There is provided an electron conductive and corrosion-resistant material 3 containing titanium (Ti), boron (B) and nitrogen (N) in an atomic ratio satisfying 0.05?[Ti]?0.40, 0.20?[B]?0.40, and 0.35?[N]?0.55 (provided that [Ti]+[B]+[N]=1). Further, there is provided a method of manufacturing an electron conductive and corrosion-resistant material 3, wherein boron nitride powder adheres to the surface of a substrate 2 of which at least the surface is made of titanium or a titanium alloy, and is then heated. Furthermore, there is provided a method of manufacturing an electron conductive and corrosion-resistant material 3, wherein the surface of a substrate 2 of which at least the surface is made of titanium or a titanium alloy is borided and then heated. In addition, there is provided a method of manufacturing an electron conductive and corrosion-resistant material 3, wherein a TiB2 layer formed of TiB2 particles is formed by spraying TiB2 powder onto a metal substrate 2 and then nitriding the TiB2 layer.

Abstract: A high-strength titanium alloy of the present invention includes Ti as a major component, 15 to 30 at % Va group element, and 1.5 to 7 at % oxygen (O) when the entirety is taken as 100 atomic % (at %), and its tensile strength is 1,000 MPa or more. Overturning the conventional concept, regardless of being high oxygen contents, it has been possible to achieve the compatibility between the high strength and high ductility on a higher level.

Abstract: A titanium alloy includes at least one alloying element whose molybdenum equivalent “Moeq” is from 3 to 11% by mass, at least one interstitial solution element selected from the group consisting of O, N and C in an amount of from 0.3 to 3% by mass, and the balance of Ti, when the entirety is taken as 100% by mass. Its content of Al is controlled to 1.8% by mass or less, and it is ? single phase at room temperature at least.

Abstract: A titanium alloy obtained by a cold-working step, in which 10% or more of cold working is applied to a raw titanium alloy, comprising a Va group element and the balance of titanium substantially, and an aging treatment step, in which a cold-worked member, obtained after the cold-working step, is subjected to an aging treatment so that the parameter “P” falls in a range of from 8.0 to 18.5 at a treatment temperature falling in a range of from 150° C. to 600° C.; and characterized in that its tensile elastic limit strength is 950 MPa or more and its elastic deformation capability is 1.6% or more. This titanium alloy is of high elastic deformation capability as well as high tensile elastic limit strength, and can be utilized in a variety of products extensively.

Abstract: A titanium alloy member is characterized in that it comprise 40% by weight or more titanium (Ti), a IVa group element and/or a Va group element other than the titanium, wherein a summed amount including the IVa group element and/or the Va group element as well as the titanium is 90% by weight or more, and one or more members made in an amount of from 0.2 to 2.0% by weight and selected from an interstitial element group consisting of oxygen, nitrogen and carbon, and that its basic structure is a body-centered tetragonal crystal or a body-centered cubic crystal in which a ratio (c/a) of a distance between atoms on the c-axis with respect to a distance between atoms on the a-axis falls in a range of from 0.9 to 1.1. This titanium alloy member has such working properties that conventional titanium alloys do not have, is flexible, exhibits a high strength, and can be utilized in a variety of products.

Abstract: A titanium alloy obtained by a cold-working step, in which 10% or more of cold working is applied to a raw titanium alloy, comprising a Va group element and the balance of titanium substantially, and an aging treatment step, in which a cold-worked member, obtained after the cold-working step, is subjected to an aging treatment so that the parameter “P” falls in a range of from 8.0 to 18.5 at a treatment temperature falling in a range of from 150° C. to 600° C.; and characterized in that its tensile elastic limit strength is 950 MPa or more and its elastic deformation capability is 1.6% or more. This titanium alloy is of high elastic deformation capability as well as high tensile elastic limit strength, and can be utilized in a variety of products extensively.

Abstract: A high-strength titanium alloy of the present invention includes Ti as a major component, 15 to 30 at % Va group element, and 1.5 to 7 at % oxygen (O) when the entirety is taken as 100 atomic % (at %), and its tensile strength is 1,000 MPa or more.

Abstract: A titanium alloy includes at least one alloying element whose molybdenum equivalent “Moeq” is from 3 to 11% by mass, at least one interstitial solution element selected from the group consisting of O, N and C in an amount of from 0.3 to 3% by mass, and the balance of Ti, when the entirety is taken as 100% by mass. Its content of Al is controlled to 1.8% by mass or less, and it is &bgr; single phase at room temperature at least.

Abstract: A titanium alloy according to the present invention is characterized in that it comprises an element of Va group (the vanadium group) in an amount of 30-60% by weight and the balance of titanium substantially, exhibits an average Young's modulus of 75 GPa or less, and exhibits a tensile elastic limit strength of 700 MPa or more. This titanium alloy can be used in a variety of products, which are required to exhibit a low Young's modulus, a high elastic deformability and a high strength, in a variety of fields.

Abstract: A titanium alloy member is characterized in that it comprises 40% by weight or more titanium (Ti), a IVa group element and/or a Va group element other than the titanium, wherein a summed amount including the IVa group element and/or the Va group element as well as the titanium is 90% by weight or more, and one or more members made in an amount of from 0.2 to 2.0% by weight and selected from an interstitial element group consisting of oxygen, nitrogen and carbon, and that its basic structure is a body-centered tetragonal crystal or a body-centered cubic crystal in which a ratio (c/a) of a distance between atoms on the c-axis with respect to a distance between atoms on the a-axis falls in a range of from 0.9 to 1.1.

Abstract: The invention relates to TiAl-base alloys with excellent oxidation resistance, and a method for producing the same. The TiAl-base alloy of the invention comprises a substrate and a surface part formed on the substrate, the surface part comprising at least one element of Cr, Nb, Ta and W and having a surface condition capable of forming a dense film of an oxide of the element or Al2O3 in high-temperature oxidizing atmospheres. The method of the invention comprises heating a TiAl-base alloy material having an Al content of from 15 at. % to 55 at. % in the presence of an oxide having a smaller negative value of standard free energy of formation than that of alumina. The method of the invention provides TiAl-base alloys with excellent oxidation resistance.

Abstract: The invention relates to TiAl-base alloys with excellent oxidation resistance, and a method for producing the same. The TiAl-base alloy of the invention comprises a substrate and a surface part formed on the substrate, the surface part comprising at least one element of Cr, Nb, Ta and W and having a surface condition capable of forming a dense film of an oxide of the element or Al2O3 in high-temperature oxidizing atmospheres. The method of the invention comprises heating a TiAl-base alloy material having an Al content of from 15 at. % to 55 at. % in the presence of an oxide having a smaller negative value of standard free energy of formation than that of alumina. The method of the invention provides TiAl-base alloys with excellent oxidation resistance. The TiAl-base alloys of the invention have significantly improved oxidation resistance and are resistant to heat at high temperatures of 900° C. or higher.

Abstract: The invention provides a method of producing an oxidation-resistant metallic part which exhibits oxidation resistance even in an oxidation atmosphere. The method includes the step of applying mechanical energy to a surface of a metallic part in the presence of particulates, and forming a protective coating in a surface of the metallic part. When the metallic part thus treated is exposed in a high temperature-oxidation atmosphere, the protective coating is oxidized to restrain the proceeding of the oxidation of the metallic part, that is the internally proceeding formation of TiO2, thus serving a remarkable improvement of the oxidation resistance.