STRUCTURE AND PROPERTIES OF THE WC - 36Co COMPOSITES PRODUCED FROM MIXTURES OF THE WC + Co AND WC + Co{sub}3O{sub}4 ULTRADISPERSED POWDERS

摘要

The compaction, structure formation and mechanical properties of the WC- 36Co wt% alloys produced from mixtures of ultradispersed powders have been studied. As the initial component of the alloy metal cobalt was used in one case and cobalt oxide in the other. The compaction has been performed mainly in the solid state by high-energy hot pressing over a wide range of temperatures. The processes of oxygen removal or the oxide reduction to the metal and high-pressure compaction have been combined into the same stage. A possibility is shown to produce dense and strong sample of the composite at low (1150 - 1250℃) temperatures. The main fundamental difference in the production of tungsten-cobalt alloy from two mixtures is the retardation of the compaction and structure formation processes in the solid-phase sintering in the case when the carbide-oxide mixture is used. Higher mechanical characteristics are exhibited by samples from the carbide-metal mixture in the solid-phase compaction, while finer-grain and homogeneous structure is observed in samples from the carbide-oxide mixture.