Ferritic stainless steel with excellent ridging resistance

Abstract

Ferritic stainless steel securing corrosion resistance while being excellent in ridging resistance able to be stably provided, that is, ferritic stainless steel with excellent ridging resistance having a composition comprising, by mass %, C: 0.001 to 0.01%, Si: 0.3% or less, Mn: 0.3% or less, P: 0.04% or less, S: 0.01% or less, Cr: 10 to 21%, Al: 0.01 to 0.2%, Ti: 0.015 to 0.3%, O: 0.0005 to 0.0050%, N: 0.001 to 0.02%, Ca: 0.0015% or less, and Mg: 0.0003% to 0.0030% and having a balance of Fe and impurities, in which steel, when defining complex inclusions including oxides and having a long axis of 1 μm or more as complex inclusions (A) and defining complex inclusions satisfying (Formula 1) to (Formula 3) in the complex inclusions (A) as complex inclusions (B), a number ratio of the number of complex inclusions (B) to the number of complex inclusions (A) satisfies (Formula 4), and among the complex inclusions (B), a number density of complex inclusions having a long axis of 2 μm or more and 15 μm or less is 2/mm2 or more and 20/mm2 or less: Al2O3/MgO≤4  (Formula 1) CaO≤20%  (Formula 2) Al2O3+MgO≥75%  (Formula 3) Number of complex inclusions (B)/Number of complex inclusions (A)≥0.70  (Formula 4) where, in (Formula 1) to (Formula 3), Al2O3, MgO, and CaO indicate the respective mass % in the oxides.

Dependencies are inferred from the claim text.