Method for fabricating fine reduced iron powders
US8940075B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 4, 2012 |
| Grant date | Jan 27, 2015 |
| Priority date | — |
| Expiry date | Mar 7, 2033 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB22F2999/00
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method for fabricating fine reduced iron powders comprises the following steps: heating fine iron oxide powders having a mean particle size of smaller than 20 μm to a reduction temperature of over 700° C. to reduce the fine iron oxide powder into iron powders that are partially sintered into iron powder agglomerates; and performing a crushing-spheroidizing process on the iron powder agglomerates to obtain individual iron powders having a mean particle size of smaller than 20 μm. The method can reduce iron oxide powers into iron powders having a rounded shape and a high packing density and a high tap density, which are suitable for the metal injection molding process and the inductor fabrication process. The reduced iron powder may further be processed using an annealing process and a second crushing-spheroidizing process in sequence to further increase the sphericity, packing density, and tap density of the reduced iron powder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.