Tungsten-carbide/cobalt based hard metals II

Methods of tungsten-carbide powder production in gaseous phase and by metal melting (Review of the professional literature) Tungsten carbide based hard metals have been produced since the 20-es of the XX century and from that time on these metals are widely applied as machining tools. In this paper we summarized production methods of tungsten carbide powders (with various cobalt content) which are the basic materials for manufacturing such tools. In the course of production from ore concentrates it is difficult to regulate the particle size of the tungsten carbide powder. The technology based on the solid/gas reaction following precipitation from watery/ethylene diamine solution is adequate for the production of WC/Co composites. The reaction of gases WCl6/CH4/H2 leads to the formation of nano-phase tungsten carbide but its efficiency is not sufficient for manufacturing at an industrial scale. Nowadays mostly the direct carbidization method is applied for manufacturing tungsten carbide powders used as basic material for the production of hard metals.