Duplex stainless steel having superior low temperature toughness
AssigneeNippon Yakin Kogyo Co., Ltd.
InventorsTakayuki Watanabe, Fugao Wei
Life of this patent
Estimating the term…
Abstract
A duplex stainless steel has reduced precipitation risks of Al nitride and Cr nitride which are undesirable precipitates, and has superior low temperature toughness. The duplex stainless steel has in mass %, indicated as “%”, C: 0.001 to 0.030%, Si: 0.05 to 0.5%, S: not more than 0.002%, Ni: 6 to 7.5%, Cr: 23 to 26%, Mo: 2 to 4.0%, N: 0.20 to 0.40%, Al: 0.005 to 0.03%, Mn: 0.05 to 0.3%, B: 0.0001 to 0.0050% and Fe, and the remainder being inevitable impurities. The duplex stainless steel has an impact value of not less than 87.5 J/cm2 at −46±2° C. as defined in Japanese Industrial Standards Z2242.
Claims16
A duplex stainless steel comprising:
- in mass %, C:
- 0.001 to 0.030%, Si:
- 0.05 to 0.5%, S:
- not more than 0.002%, Ni:
- 6.39 to 7%, Cr:
- 23 to 26%, Mo:
- 2 to 4.0%, N:
- 0.20 to 0.40%, Al:
- 0.005 to 0.03%, Mn:
- 0.05 to 0.3%, B:
- 0.0001 to 0.0050%, Cu:
- 0.01 to 0.90%, inevitable impurities and Fe being remainder,
- wherein an impact value defined in Japanese Industrial Standards Z2242 is controlled to be not less than 87.5 J/cm2 at −46±2° C.
Dependencies are inferred from the claim text.