Stratified enriched zones formed by the gas phase carburization and the slow cooling of cemented carbide substrates, and methods of manufacture
US5494635A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 20, 1993 |
| Grant date | Feb 27, 1996 |
| Priority date | — |
| Expiry date | May 20, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12021
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Processes are disclosed in which cemented carbide parts, having a wide range of initial carbon levels, and a wide range of sizes, can be carburized to a critical carbon level, and then slow cooled at various rates, to yield stratified enriched zones in the near-surface region of said parts. The enriched zones are characterized by the cobalt content decreasing, and the microhardness increasing, continuously through the enriched zones, and approaching values characteristic of the interior. The combination of stratified enriched zones in the near surface region and the 6% binder interior provide the toughness and deformation resistance required for heavy roughing applications. A wide variety of cemented carbides, having different compositions and WC grain sizes, can also be carburized and slow cooled using the same techniques to yield stratified binder enriched zones having the same hardness profiles and cobalt content profiles as described above.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.