Ferritic stainless steel excellent in heat resistance property and formability

Abstract

An object is to provide ferritic stainless steel excellent in heat resistance (oxidation resistance, a thermal fatigue property and a high-temperature fatigue property) and formability, while preventing a decrease in oxidation resistance due to Cu, without adding expensive chemical elements such as Mo and W. Specifically, ferritic stainless steel having a chemical composition containing, by mass %, C: 0.015% or less, Si: 0.4% or more and 1.0% or less, Mn: 1.0% or less, P: 0.040% or less, S: 0.010% or less, Cr: 12% or more and less than 16%, N: 0.015% or less, Nb: 0.3% or more and 0.65% or less, Ti: 0.15% or less, Mo: 0.1% or less, W: 0.1% or less, Cu: 1.0% or more and 2.5% or less and Al: 0.2% or more and 1.0% or less, while the relationship Si≧Al is satisfied, and the balance being Fe and inevitable impurities.

1 . Ferritic stainless steel having a chemical composition containing, by mass %, C: 0.015% or less, Si: 0.4% or more and 1.0% or less, Mn: 1.0% or less, P: 0.040% or less, S: 0.010% or less, Cr: 12% or more and less than 16%, N: 0.015% or less, Nb: 0.3% or more and 0.65% or less, Ti: 0.15% or less, Mo: 0.1% or less, W: 0.1% or less, Cu: 1.0% or more and 2.5% or less and Al: 0.2% or more and 1.0% or less, while the relationship Si≧Al is satisfied, and the balance being Fe and inevitable impurities. 
     
     
         2 . Ferritic stainless steel having a chemical composition further containing one, two or more chemical elements selected from among, by mass %, B: 0.003% or less, REM: 0.08% or less, Zr: 0.5% or less, V: 0.5% or less, Co: 0.5% or less and Ni: 0.5% or less.