Martensitic Stainless Steel with High Strength, High Toughness and High Corrosion Resistance

A method of producing a martensitic stainless steel comprising:

• providing a steel comprising in mass %, C:
• 0.005% to 0.05%, Si:
• equal to or less than 1.0%, Mn:
• equal to or less than 2.0%, Cr:
• 16 to 18%, Ni:
• 2.5 to 6.5%, Mo:
• 1.5 to 3.5%, W:
• equal to or less than 3.5%, Cu:
• equal to or less than 3.5%, V:
• 0.01 to 0.08%, Sol.Al:
• 0.005 to 0.10%, N:
• equal to or less than 0.05%, and Ta:
• 0.01 to 0.06%, and the balance Fe with inevitable impurities;
• hot-working the steel;
• heating the hot-worked steel to form austenite in the hot-worked steel at a temperature equal to or higher than 800° C. and equal to or lower than 980° C.;
• quenching and cooling the heated steel at a temperature equal to or lower than 100° C.;
• and
• tempering the quenched steel at a temperature equal to or higher than 500° C. and equal to or lower than 700° C.