Patent ID: 11834725

Abstract:
The martensitic stainless steel material has a chemical composition, which contains: in mass %, C: 0.030% or less, Si: 1.00% or less, Mn: 1.00% or less, P: 0.030% or less, S: 0.005% or less, Al: 0.010 to 0.100%, N: 0.0010 to 0.0100%, Ni: 5.00 to 6.50%, Cr: 10.00 to 13.40%, Cu: 1.80 to 3.50%, Mo: 1.00 to 4.00%, V: 0.01 to 1.00%, Ti: 0.050 to 0.300%, Co: 0.300% or less, Ca: 0.0006 to 0.0030%, and O: 0.0050% or less, and satisfies Formulae (1) and (2) in the description. An area of each intermetallic compound and each Cr oxide in the steel material is 5.0 μm2 or less, a total area fraction of intermetallic compounds and Cr oxides is 3.0% or less, and a maximum circle-equivalent diameter of Ca oxide is 9.5 μm or less.