Abstract: The present invention provides a metal wire rod composed of iridium or an iridium alloy, wherein the number of crystal grains on any cross-section in a longitudinal direction is 2 to 20 per 0.25 mm2, and the Vickers hardness at any part is 200 Hv or more and less than 400 Hv. The iridium wire rod is a material which is produced by a ?-PD method, and has low residual stress and which has a small change in the number of crystal grains and hardness even when heated to a temperature equal to or higher than a recrystallization temperature (1200° C. to 1500° C.). The metal wire rod of the present invention is excellent in oxidative consumption resistance under a high-temperature atmosphere, and mechanical properties.

Abstract: The present invention relates to a NiIr-base heat-resistant alloy which includes a Ni—Ir—Al—W-base alloy which contains Ir: 5.0 to 50.0 mass %, Al: 1.0 to 8.0 mass %, W: 5.0 to 20.0 mass %, and the balance is Ni, and a ?? phase having an L12 structure precipitating and dispersing in a matrix as an essential strengthening phase, and a ratio (Y/X) of a peak intensity (Y) of (201) plane of the Ir3W phase observed in the range of 2?=48° to 50° to a peak intensity (X) of (111) plane of the ?? phase observed in the range of 2?=43° to 45° in X-ray diffraction analysis is 0.5 or less. The alloy exhibits good high-temperature property stably.

Abstract: The present invention is a heat-resistant Ni-base alloy including a Ni—Ir—Al—W alloy having essential additive elements of Ir, Al, and W added to Ni, wherein the heat-resistant Ni-base alloy includes Ir: 5.0 to 50.0 mass %, Al: 1.0 to 8.0 mass %, and W: 5.0 to 20.0 mass %, the balance being Ni, and a ?? phase having an L12 structure disperses in a matrix as an essential strengthening phase. The heat-resistant material including the Ni-base alloy may contain one or more additive elements selected from B: 0.001 to 0.1 mass %, Co: 5.0 to 20.0 mass %, Cr: 1.0 to 25.0 mass %, Ta: 1.0 to 10.0 mass %, Nb: 1.0 to 5.0 mass %, Ti: 1.0 to 5.0 mass %, V: 1.0 to 5.0 mass %, and Mo: 1.0 to 5.0 mass %, or 0.001 to 0.5 mass % of C.

Abstract: The present invention is a metallic wire rod comprising iridium or an iridium-containing alloy and, the wire rod has in the cross section thereof biaxial crystal orientation of 50% or more of abundance proportion of textures in which crystallographic orientation has preferred orientation to <100> direction. In the present invention, crystal orientation in the outer periphery from semicircle of the cross section which is the periphery of the wire rod is important, and in this zone, abundance proportion of textures in which crystallographic orientation has preferred orientation to <100> direction is preferably not less than 50%.

Abstract: The present invention relates to a NiIr-base heat-resistant alloy which includes a Ni—Ir—Al—W-base alloy which contains Ir: 5.0 to 50.0 mass %, Al: 1.0 to 8.0 mass %, W: 5.0 to 20.0 mass %, and the balance is Ni, and a ?? phase having an L12 structure precipitating and dispersing in a matrix as an essential strengthening phase, and a ratio (Y/X) of a peak intensity (Y) of (201) plane of the Ir3W phase observed in the range of 2?=48° to 50° to a peak intensity (X) of (111) plane of the ?? phase observed in the range of 2?=43° to 45° in X-ray diffraction analysis is 0.5 or less. The alloy exhibits good high-temperature property stably.

Abstract: The present invention provides a metal wire rod composed of iridium or an iridium alloy, wherein the number of crystal grains on any cross-section in a longitudinal direction is 2 to 20 per 0.25 mm2, and the Vickers hardness at any part is 200 Hv or more and less than 400 Hv. The iridium wire rod is a material which is produced by a ?-PD method, and has low residual stress and which has a small change in the number of crystal grains and hardness even when heated to a temperature equal to or higher than a recrystallization temperature (1200° C. to 1500° C.). The metal wire rod of the present invention is excellent in oxidative consumption resistance under a high-temperature atmosphere, and mechanical properties.

Abstract: The present invention is a heat-resistant Ni-base alloy including a Ni—Ir—Al—W alloy having essential additive elements of Ir, Al, and W added to Ni, wherein the heat-resistant Ni-base alloy includes Ir: 5.0 to 50.0 mass %, Al: 1.0 to 8.0 mass %, and W: 5.0 to 20.0 mass %, the balance being Ni, and a ?? phase having an L12 structure disperses in a matrix as an essential strengthening phase. The heat-resistant material including the Ni-base alloy may contain one or more additive elements selected from B: 0.001 to 0.1 mass %, Co: 5.0 to 20.0 mass %, Cr: 1.0 to 25.0 mass %, Ta: 1.0 to 10.0 mass %, Nb: 1.0 to 5.0 mass %, Ti: 1.0 to 5.0 mass %, V: 1.0 to 5.0 mass %, and Mo: 1.0 to 5.0 mass %, or 0.001 to 0.5 mass % of C.

Abstract: The present invention is a metallic wire rod comprising iridium or an iridium-containing alloy and, the wire rod has in the cross section thereof biaxial crystal orientation of 50% or more of abundance proportion of textures in which crystallographic orientation has preferred orientation to <100> direction. In the present invention, crystal orientation in the outer periphery from semicircle of the cross section which is the periphery of the wire rod is important, and in this zone, abundance proportion of textures in which crystallographic orientation has preferred orientation to <100> direction is preferably not less than 50%.

Abstract: A material for a plug electrode having not only excellent oxidation wear resistance but also excellent spark wear, and also having adequately-considered discharge properties in use is provided. The present invention relates to a material for a plug electrode, comprising 5% by mass or more and 30% by mass or less of Cu, 0.1% by mass or more and 15% by mass or less of Ir, with the balance being Pt. Alloying by combining two metals of Cu and Ir can reduce discharge voltages and improve durability against spark wear. With addition of only one of them, the effect of improving spark wear properties is poor and the effect of reducing discharge voltages cannot be expected.