Patent · US Expired

Method for heat-treating steel work pieces

US6187118A · kind A · utility

3Cited by
5References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 28, 1999
Grant dateFeb 13, 2001
Priority date
Expiry dateOct 28, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/25
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A method of heat-treating a work piece of high-alloy steel by hardening involves relatively briefly annealing the work piece before hardening, followed by cooling the work piece. The brief annealing that is performed before the actual hardening and the ensuing cooling results in homogeneity of the material in the microscopic range. Following the annealing, the work piece is hardened, for instance by quenching in a salt bath, to achieve a super fine distribution of globular carbides in the microscopic structure with considerably reduced size as compared to the outset state. Also, the microscopic structure created by the method of the invention has improved toughness properties as well as increased microscopic structure stability to aging and leads to a longer service life.

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