Method of making cemented carbide
AssigneeSandvik AB
InventorsMikael Lindholm, Mats Waldenström, Mats Ahlgren
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Abstract
The present invention relates to a method of making a cemented carbide by mixing powder of WC and possibly other powders forming hard constituents and binder phase and pressing agent, drying, pressing and sintering whereby; the mixing is wet mixing with no change in grain size or grain size distribution of the hard constituent powders; the WC grains are coated with binder metal and deagglomerated prior to the mixing. The sintering is made by microwave sintering at 1325-1410° C. with a holding time of 5-15 min. As a result a cemented carbide with improved properties is obtained.
Claims21
A method of making a cemented carbide comprising:
- providing a powder forming hard constituents;
- coating the hard constituent powder with binder phase material;
- deagglomerating the coated powder;
- wet mixing the coated powder with additional constituents such that no change in grain size or grain size distribution of the hard constituent powders is produced;
- drying the mixture;
- forming a green body with the dried mixture;
- and
- sintering the body in a microwave field at a temperature of 1325-1410° C. for approximately 5-15 minutes.
The method according to claim 6, wherein the WC-powder has a narrow grain size distribution such that dmax-dmin<2 μm.
The method according to claim 5, wherein the WC-powder has a biomodal grain size distribution.
The method according to claim 5, wherein the cemented carbide has a binder phase enriched surface zone.
A method of making a cemented carbide comprising:
- providing a carbide powder;
- coating the carbide powder with binder phase material;
- deagglomerating the coated powder;
- wet mixing the coated powder with additional constituents such that no change in grain size or grain size distribution of the hard constituent powders is produced;
- drying the mixture;
- forming a green body with the dried mixture;
- and
- sintering the body in a microwave field at a temperature of 1325-1410° C. for approximately 5-15 minutes.
Dependencies are inferred from the claim text.