Patent · US Expired

Stainless steel

US5888449A · kind A · utility

7Cited by
2References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 1997
Grant dateMar 30, 1999
Priority date
Expiry dateMay 30, 2017

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC21D2211/008
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Precipitation hardening (PH) stainless steels heat treatable to yield strength levels in the range of 200 ksi with exceptionally high fracture toughness are achieved in alloys consisting essentially of 12.25-13.25% chromium, 7.5-8.5% nickel, 2.0-2.5% molybdenum, 0.8-1.35% aluminum, not over 0.05% carbon, not over 0.10% silicon, not over 0.10% manganese, not over 0.010% phosphorus and with especially critical amounts of not over 0.0020% (20 ppm) nitrogen, not over 0.0020% (20 ppm) sulfur, not over 0.0026% (26 ppm) nitrogen plus sulfur; not over 0.04% titanium, and remainder essentially Fe.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.