| 摘要 |
This Ni-based alloy is constituted of chemical components which comprise C, Si, Mn, Cr, Mo, Co, Al, Ti, B, P, S, and, as the remainder, Ni and impurities. If the average crystal grain diameter, in unit of µm, of the gamma phase contained in the metallographic structure of this Ni-based alloy is expressed by d, the average crystal grain diameter d is 10-300 µm. This metallographic structure has no precipitate grains that have a major-axis length of 100 nm or larger. If the grain boundary coverage index represented by the average crystal grain diameter d and by the contents, in mass%, of some elements among the chemical components is expressed by rho, this grain boundary coverage index rho is equal to or greater than the value of f2 which is represented by the average crystal grain diameter d and by the contents, in mass%, of some elements among the chemical components. |
