| 摘要 |
A Ni-based alloy includes, as a chemical composition, C, Si, Mn, Cr, Mo, Co, Al, Ti, B, P, S, and a balance consisting of Ni and impurities. The average grain size d is 10 μm to 300 μm, when the average grain size d is an average grain size in unit of μm of a γ phase included in a metallographic structure of the Ni-based alloy. Precipitates with a major axis of 100 nm or more are absent in the metallographic structure. An area fraction ρ is f2 or more, when the area fraction ρ and the f2 are expressed by using the average grain size d and amounts in mass% of each element in the chemical composition. |
| 主权项 |
1. A Ni-based alloy comprising, as a chemical composition, by mass %,
0.001% to 0.15% of C, 0.01% to 2% of Si, 0.01% to 3% of Mn, 15% to less than 28% of Cr, 3% to 15% of Mo, more than 5% to 25% of Co, 0.2% to 2% of Al, 0.2% to 3% of Ti, 0.0005% to 0.01% of B, 0% to 3.0% of Nb, 0% to 15% of W, 0% to 0.2% of Zr, 0% to 1% of Hf, 0% to 0.05% of Mg, 0% to 0.05% of Ca, 0% to 0.5% of Y, 0% to 0.5% of La, 0% to 0.5% of Ce, 0% to 0.5% of Nd, 0% to 8% of Ta, 0% to 8% of Re, 0% to 15% of Fe, f1 expressed by a following Expression 1 or less of P, 0.01% or less of S, and a balance consisting of Ni and impurities, wherein, when an average grain size d is an average grain size in unit of μm of a γ phase included in a metallographic structure of the Ni-based alloy, the average grain size d is 10 μm to 300 μm, wherein precipitates with a major axis of 100 nm or more are absent in the metallographic structure, and wherein, when an area fraction ρ is expressed by a following Expression 2 using the average grain size d and amounts in unit of mass % of each element in the chemical composition, the area fraction ρ is f2 expressed by a following Expression 3 or more,
f1=0.01−0.012/[1+exp{(B−0.0015)/0.001}] (Expression 1),ρ=21×d0.15+40×(500×B/10.81+50×C/12.01+Cr/52.00)0.3 (Expression 2),f2=32×d0.07+115×(Al/26.98+Ti/47.88+Nb/92.91)0.5 (Expression 3). |
