Die lubricant and iron-based powder mixture for warm compaction with die lubrication, and processes for producing high-density iron-based green and sintered compacts
US6355208B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2000 |
| Grant date | Mar 12, 2002 |
| Priority date | — |
| Expiry date | Aug 2, 2020 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB22F2999/00
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for producing a high-density iron-based green compact is provided that can form a green compact with a high density. Also provided is a process for producing a sintered compact from the green compact. A specified combination lubricant is applied to the surface of a die for compacting by electrical charging, wherein the combination lubricant includes a first lubricant having a melting point that is higher than a preset compacting temperature, and a second lubricant having a melting point that is lower than a compacting temperature. A heated iron-based powder mixture is filled into the die, followed by compacting, whereby a green compact is formed. The green compact can be sintered to provide a sintered compact. The powder mixture comprises an iron-based powder, a lubricant and a graphite powder, wherein the lubricant includes a first lubricant having a melting point that is lower than the compacting temperature and in an amount from 10 to 75% by mass, and a second lubricant having a melting point that is higher than the compacting temperature, and the content of the graphite powder is less than 0.5% by mass based on the total amount of the iron-based powder mixture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.