High corrosion resistance Ni-Cr-Mo-N alloy with excellent phase stability

摘要

PROBLEM TO BE SOLVED: To provide a Ni—Cr—Mo—N alloy having excellent corrosion resistance even when exposed to a temperature range in which a sigma phase is precipitated, specifically, a temperature range of 700 to 1000 ° C. SOLUTION: Ni: 22.0% or more, Cr: 22.0% or more, Mo: 5.0% or more, N: 0.180% or more, Si, Al, Mn are contained in the following mass%. The balance is an alloy composed of Fe and unavoidable impurities, and the area ratio of the sigma phase measured by EBSD in the cross-sectional structure after satisfying the following formulas (1) to (3) and holding at 950 ° C. × 30 min. A Ni—Cr—Mo—N alloy, characterized in that the content is 1.0% or less. Cr + 3.3 × Mo + 16 × N ≧ 43.0… (1) 7.3 × Mo-Ni ≦ 21.0… (2-1) 1.3 × Cr-Ni ≦ 5.7… (2-2) 1.6 × Si + 0.99 × Mn + 2.2 × Al ≦ 0.95… (3) [Selection diagram] Fig. 1