High Cr low Ni two-phased cast stainless steel
AssigneeKubota Corporation
InventorsShinichi Murakami, Toshiaki Morichika, Hisashi Hiraishi, Hiroyuki Shiokawa
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Abstract
Ferrite-austenitic two-phased stainless steel with high corrosion resistance and toughness containing the following, which may be manufactured easily by furnace melting in the atmosphere composition (by weight %) ______________________________________ C less than 0.10% Si less than 1.5% Mn less than 1.5% P less than 0.04% S less than 0.04% Cr 22-30% Ni 3-6% Mo 0.5-1.5% Cu 0.4-1.0% N less than 0.1% Nb 0.1-0.24% Fe Balance and Creq/Nieq is 3-4.5 Ferrite content is 50-80% ______________________________________
Claims7
A ferrite-austenitic two-phased cast stainless steel having an impact strength of at least 3 kg-m/cm.sup.2 and containing the following (weight %):
- ______________________________________ C less than 0.10% Si less than 1.5% Mn less than 1.5% P and S less than 0.4% each Cr 22-30% Ni 3-6% Mo 0.5-0.9% Cu 0.4-1.0% N less than 0.1% Nb 0.1-0.24% Fe balance ______________________________________
- wherein values of Ni equivalent and Cr equivalent are calculated by the following equations:
- Cr eq=Cr%+Mo%+1.5 Si%+0.5 Nb%
- Ni eq=Ni%+0.5 Mn%+30 C%
- Cr eq/Ni eq being 3 to 4.5 and ferrite content being 50 to 80%.
A ferrite-austenitic two-phased cast stainless steel having an impact strength of at least 3 kg-m/cm.sup.2 and containing the following (weight %):
- ______________________________________ C less than 0.10% Si less than 1.5% Mn less than 1.5% P and S less than 0.04% each Cr 22-30% Ni 3-6% Mo 0.5-0.9% Cu 0.4-1.0% N less than 0.1% Nb 0.1-0.24% Al or Ca or both less than 0.1% Fe balance ______________________________________
- wherein values of Ni equivalent or Cr equivalent are calculated by the following equations:
- Cr eq=Cr%+Mo%+1.5 Si%+0.5 Nb%
- Ni eq=Ni%+0.5 Mn%+30 C%
- Cr eq/Ni eq being 3 to 4.5 and ferrite content being 50 to 80%.
Dependencies are inferred from the claim text.