Abstract: A method for manufacturing a hypoid gear includes: a tooth cutting step of machining a shape of a tooth of the hypoid gear; a surface treatment step of forming a third intermediary gear provided with a hardened layer on a surface of the tooth; a lapping step of machining the third intermediary gear using an abrasive particle having a diameter of 14 ?m or less to form a fourth intermediary gear; and a shot peening step of spraying a particle having a diameter of 160 ?m or less onto the fourth intermediary gear.

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: Aluminum alloys and castings are provided that have excellent practical fatigue resistances. The alloy includes, based upon 100 mass %, 4-12 mass % of Si, less than 0.2 mass % of Cu, 0.1-0.5 mass % of Mg, 0.2-3.0 mass % of Ni, 0.1-0.7 mass % of Fe, 0.15-0.3 mass % of Ti, and the balance of aluminum (Al) and impurities. The alloy has a metallographic structure, which includes a matrix phase primarily of ?-Al and a skeleton phase crystallizing around the matrix phase in a network shape. The matrix phase is strengthened by precipitates containing Mg. Because of the strengthened matrix phase, and the skeleton phase that surrounds it, the castings have high strength, high fatigue strength, and high thermo-mechanical fatigue resistance.

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 compressor having a housing formed by a plurality of housing members that are connected together is disclosed. The compressor is configured in such a manner that refrigerant is compressed in the housing and discharged to the exterior. Each of the housing members contains 9 to 17 percent by mass of Si, 3.5 to 6 percent by mass of Cu, 0.2 to 1.2 percent by mass of Mg, 0.2 to 1.5 percent by mass of Fe, 0 to 1 percent by mass of Mn, 0.5 percent by mass or less of Ni, and a remaining portion containing Al and unavoidable impurities. It is preferred that the average hardness of each housing member is adjusted to HV130 to HV170 through solution heating in which the housing member is maintained at the treatment temperature of 450° C. to 510° C. for 0.5 hours or longer, followed by water quenching, and then by aging treatment in which the housing member is maintained at the treatment temperature of 170° C. to 230° C. for one to twenty-four hours after the c housing member is cast.

Abstract: A cast aluminum alloy excellent in the relaxation resistance property, comprising 9 to 17% by mass of Si, 3 to 6% by mass of Cu, 0.2 to 1.2% by mass of Mg, 0.2 to 1.5% by mass of Fe, 0.1 to 1% by mass of Mn, a balance consists of Al and unavoidable impurities, wherein a Ni content is not more than 0.5% by mass. The average hardness is adjusted to HV130 to HV160 by performing, after casting, solution heating by retaining the alloy at a treatment temperature of 450 to 510° C. for 0.5 hour or longer, performing water quenching and, thereafter, performing aging treatment by retaining the alloy at a treatment temperature of 170 to 230° C. for 1 to 24 hours.

Abstract: Aluminum alloys and castings are provided that have excellent practical fatigue resistances. The alloy includes, based upon 100 mass %, 4-12 mass % of Si, less than 0.2 mass % of Cu, 0.1-0.5 mass % of Mg, 0.2-3.0 mass % of Ni, 0.1-0.7 mass % of Fe, 0.15-0.3 mass % of Ti, and the balance of aluminum (Al) and impurities. The alloy has a metallographic structure, which includes a matrix phase primarily of ?-Al and a skeleton phase crystallizing around the matrix phase in a network shape. The matrix phase is strengthened by precipitates containing Mg. Because of the strengthened matrix phase, and the skeleton phase that surrounds it, the castings have high strength, high fatigue strength, and high thermo-mechanical fatigue resistance.

Abstract: A process for manufacturing a sheet having a chip-like design composed of a plurality of chips densely aligned in a plane without overlapping and a solidified binder uniformly filling the interstices among the chips and firmly and integrally bonding the chips to one another in sheet form. The sheet is useful as a floor material, wall material, and the like.