PRODUCTION METHOD FOR AUSTENITIC HEAT-RESISTANT ALLOY WELD JOINT, AND WELD JOINT OBTAINED THEREBY

摘要

PROBLEM TO BE SOLVED: To provide a production method for an austenitic heat-resistant alloy weld joint excellent in creep strength and stress relaxation crack resistance, and to provide the weld joint obtained thereby.SOLUTION: A production method for an austenitic heat-resistant alloy weld joint, comprises: welding an austenitic alloy base material having the prescribed chemical ingredients by using the welding material having a chemical component comprising in mass%, 0.06-0.18% C, 1.0% or less Si, 2.0% or less Mn, 0.03% or less P, 0.01% or less S, 40.0-60.0% Ni, 20.0-26.0% Cr, 6.0-13.0% total of Mo and/or W, 0.05-0.6% Ti, 1.5% or less Al, 0.18% or less N, 0.01% or less O, 0-15.0% Co, 0-0.5% Nb, 0-0.005% B, and the balance Fe with impurities; and carrying out a post-welding heat treatment in which a post-welding heat treatment temperature T (°C), a post-welding heat treatment time t (min), and an average temperature-lowering speed RC (°C/h) from T to 500°C satisfy [800≤T≤1250], [-0.2×T+270≤t≤-0.6×T+810], and [RC≥0.05×T-10].SELECTED DRAWING: None