Patent · US Expired

Carbo-nitrided case hardened martensitic stainless steels

US7186304B2 · kind B2 · utility

21Cited by
2References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 2, 2004
Grant dateMar 6, 2007
Priority date
Expiry dateJul 12, 2024

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16C2204/70
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A carbo-nitriding process for forming a martensitic stainless steel, which is case hardened and superior corrosion resistance over carburized process, is provided. A process for forming a martensitic stainless steel which is case hardened is provided. The process comprises the steps of providing a material consisting essentially of from 8.0 to 18 wt % chromium, cobalt up to 16 wt %, vanadium up to 5.0 wt %, molybdenum up to 8.0 wt %, nickel up to 8.0 wt %, manganese up to 4.0 wt %, silicon up to 2.0 wt %, tungsten up to 6.0 wt %, titanium up to 2.0 wt %, niobium up to 4.0 wt % and the balance iron, and carbo-nitriding to prescribed levels of C+N, to form a hard, corrosion resistance case in a fracture tough stainless steel.

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