Corrosion-resistant sintered alloy steels and method for making same
US5108492A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 1990 |
| Grant date | Apr 28, 1992 |
| Priority date | — |
| Expiry date | Feb 22, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB22F2201/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
It is provided a method for the manufacture of a corrosion-resistant sintered alloy steel, which comprises providing a stainless steel powder; adding a binder to said steel powder; molding the mixture; and carrying out the steps of (1) heating the resultant molding to remove the binder therefrom, (2) sintering the thus debound molding under reduced pressure up to 30 Torr, and (3) further sintering at a higher temperature than those of steps (1) and (2) in a non-oxidative atmosphere under substantially atmospheric pressure. It is also provided a corrosion-resistant sintered alloy steel which comprises a stainless steel, said alloy steel having a density ratio of not less than 92%, a maximum diametric of pore present in the structure of not larger than 20 .mu.m, and a content of Cr at the surface of the steel as being sintered which is not less than 80% of a content of Cr in the inside thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.