Patent · US Expired

High carbon, high density forming

US5997805A · kind A · utility

9Cited by
7References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 19, 1997
Grant dateDec 7, 1999
Priority date
Expiry dateJun 19, 2017

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB22F2998/00
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A manufacturing method is provided for the production of high density, high carbon, sintered powder metal steels. The composition consists of iron based powder, graphite, lubricant, and possibly at least one alloying element from the group of chromium, copper, manganese, molybdenum, nickel, niobium or vanadium. The composition is compacted in rigid tools, sintered and during cooling an isothermal or slow cooling treatment is introduced between 650.degree. C. and 750.degree. C. The isothermal or slow cooling treatment may alternatively be applied during a heat treatment cycle that is carried out after a conventional sintering cycle. The material processed as described may then be formed to high density. Forming to high density is not practical with high carbon materials that have been processed by conventional methods. The high density article is then heat treated in a manner to suit specific product requirements. The mechanical properties achieved by the claimed process offer significant benefits when compared to conventionally processed sintered powder metal articles.

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