1.8∼7.8 mol%MoS
2 is added to WC-20 mol%Co of a basic alloy system to develop cemented carbides having the ability of self-lubrication, where MoS
2 is well known as one of the solid lubricants. The spark sintering has been applied to the sintering of these MoS
2 containing carbides. The evaluation of microstructures, the hardness and charpy impact tests are also carried out on the spark sintered compacts. The results obtained from this study are summarized as follows. The conditions selected as the optimum sintering condition for WC-20Co. are: The number of pulse is 3000 for preliminary treatment of powders, and the resistance sintering temperature and time are 1473 K and 0.6 ks, respectively, where the decreasing rate of specific resistivity of compacts is a guide to the determination of the number of pulse, and the microstructure, displacement of densification and hardness are guides to the determination of the resistance sintering conditions. These conditions are also used in the spark sintering process of MoS
2 containing carbides. Only three materials, WC, Co and MoS
2, are identified in the compacts which are sintered under the conditions mentioned above. It is considered that the exposed period of compacts are short (0.6 ks) at the maximum sintering temperature (1473 K) and single or condensed particles of MoS
2 are surrounded by WC-Co compacts whose relative densities are more than 70% at the thermal decomposition temperature (approximately 1273 K), which lead to the residue of MoS
2 in the sintered compacts. On the other hand, the hardness and Charpy impact values have a tendency of decreasing with the MoS
2 content in carbides. In particular, the rate of decrease of these values are larger for the compacts low in the content of MoS
2.
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