FERRITIC STAINLESS STEEL HAVING EXCELLENT CORROSION RESISTANCE IN CONDENSED WATER ENVIRONMENT PRODUCED BY EXHAUST GAS FROM HYDROCARBON COMBUSTION

摘要

The present invention provides a ferritic stainless steel exhibiting excellent corrosion resistance in a condensed water environment arising from a hydrocarbon combustion exhaust gas typified by the use environment of a structural member of a secondary heat exchanger, which stainless steel is a ferritic stainless steel comprising, in mass%, C: 0.030% or less, N: 0.030% or less, Si: 0.4% or less, Mn: 0.01 to 0.5%, P: 0.05% or less, S: 0.01% or less, Cr: 16 to 24%, Mo: 0.30 to 3%, Ti: 0.05 to 0.25%, Nb: 0.05 to 0.50%, Al: 0.01 to 0.2%, and Cu: 0.4% or less, the balance being Fe and unavoidable impurities, and satisfying Expression (A): Cr + Mo + 10Ti ≥ 18 and Expression (B): Si + Cu ≤ 0.5.