Ferritic stainless steel

摘要

Provided is a ferritic stainless steel excellent in terms of thermal fatigue resistance and oxidation resistance without adding Mo or W, which is an expensive chemical element and with controlling the Nb content to be as small as possible. The chemical composition contains, by mass %, C: 0.020% or less, Si: 3.0% or less, Mn: 3.0% or less, P: 0.040% or less, S: 0.030% or less, Cr: 10% to 25%, N: 0.020% or less, Nb: 0.005% to 0.15%, Al: less than 0.20%, Ti: 5×(C %+N %) to 0.5%, Mo: 0.1% or less, W: 0.1% or less, Cu: 0.55% to 2.0%, B: 0.0002% to 0.0050%, Ni: 0.05% to 1.0%, and the balance being Fe and inevitable impurities, where C % and C5 in the expression 5×(C %+N %) respectively represent the contents (mass %) of the chemical elements C and N.

主权项

1. Ferritic stainless steel having a chemical composition containing, by mass %, C: 0.005% to 0.020%, Si: 3.0% or less, Mn: 3.0% or less, P: 0.040% or less, S: 0.030% or less, Cr: 10% to 25%, N: 0.006% to 0.020%, Nb: 0.005% to 0.08%, Al: less than 0.20%, Ti: 5×(C %+N %) to 0.5%, Mo: 0.1% or less, W: 0.1% or less, Cu: 0.55% to 2.0%, B: 0.0002% to 0.0050%, Ni: 0.05% to 1.0%, and the balance being Fe and inevitable impurities, where C % and N % in the expression 5×(C %+N %) respectively represent the contents (mass %) of the chemical elements C and N, wherein the ferritic stainless steel exhibits a weight gain by oxidation of less than 50 g/m2.