Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10626481 | Ceramics International | 2005 | 7 Pages |
Abstract
Tungsten carbide nanopowders were synthesized successfully by electric discharge machining followed by annealing under a nitrogen atmosphere. The tungsten workpieces were initially melted and evaporated on the working surface during the electric discharge machining process, and then the tungsten powders were reacted with the carbon electrode and the working medium of kerosene to form the nanocrystalline WC1âx powders. The powders produced were characterized by XRD, SEM, and TEM. When annealing the powders under an N2 atmosphere, the cubic phases of WC1âx gradually changed to hexagonal W2C and then were transformed fully to nanocrystalline hexagonal WC at 1200 °C, with the nanocrystalline tungsten carbide encapsulated in a carbon shell. On the other hand, under an H2 atmosphere, the WC1âx phase changed via a W2C phase to reduced powders of pure tungsten at 1000 °C or were reduced directly from WC1âx to elemental W.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Ming-Hong Lin,