Patent ID: 6723181
Filing Date: 2004-04-20
Classification: C21D,C22C

Abstract:
A soft stainless steel sheet excellent in workability and cold-forgability, which has an austenite-stability index Md30, which is defined by formula (1), adjusted in a range of âˆ’120 to âˆ’10, a stacking fault formability index SFI, which is defined by the formula (2), adjusted at a value not less than 30 and Cu concentration of precipitates not more than 1.0 mass % so as to maintain Cu content dissolved in a matrix at 1.0-4.0 mass %, wherein 70 mass % or more of nonmetallic inclusions precipitated in the matrix are MnOâ€”SiO2â€”Al2O3 containing not less than 15 mass % of SiO2 and not more than 40 mass % of Al2O3 Md30(Â° C.)=551âˆ’462(C+N)âˆ’9.2Siâˆ’8.1Mnâˆ’29(Ni+Cu)âˆ’13.7Crâˆ’18.5Moâ€ƒâ€ƒ(1) SFI(mJ/m2)=2.2Ni+6Cuâˆ’1.1Crâˆ’12Siâˆ’1.2Mn+32â€ƒâ€ƒ(2).