Surface densification of machine components made by powder metallurgy
US6013225A · kind A · utility
18Cited by
17References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 12, 1999 |
| Grant date | Jan 11, 2000 |
| Priority date | — |
| Expiry date | Apr 12, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2221/10
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A sintered powder metal part is surface densified by surface heating followed by repressing. Surface heating is preferably done to a temperature which is just below the critical temperature where the steel alloy material of the part transforms from a ferritic to an austenitic microstructure. Repressing is in a die set which is smaller than the part by 10% of the surface heated depth. The hot skin is compressed and densified between the die and the cooler, and therefore less malleable core of the part Following surface densification, the part may be resintered and/or heat treated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.