Cold forced sintered powder metal annular bearing ring blanks
US4393563A · kind A · utility
Inventor
Key dates
| Filing date | May 26, 1981 |
| Grant date | Jul 19, 1983 |
| Priority date | — |
| Expiry date | May 26, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49689
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method and material for the manufacture of improved bearing elements such as annular inner and outer bearing ring blanks for ball, roller and needle bearing assemblies comprising the steps of mixing a powder consisting substantially of iron with ferro-alloy powders of substantially smaller size, each ferro-alloy containing at least 80% iron and the balance being an alloying element, together with graphite powder and a lubricant, compacting the resulting mixture to form a preform, pre-sintering the preform, and then coating the sintered preform with a stop-off and lubricant. The preform is subjected to a plastic deformation of at least 50% in a cold (room temperature) forging operation to produce an article which is at least 98% dense and has approximately the shape of the finished article. This cold forged shape is resintered and annealed, after which the annealed and resintered shape is roll formed into substantially final dimensions. The article can be followed by a suitable heat treatment for hardening the shape.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.