Omkar Metal Corporation

Cemented Carbide At present, tungsten in the form of tungsten carbide is mainly used in the production of cemented carbide. Cemented carbide, (also referred to as hard metal), is a material created by “cementing” very hard tungsten monocarbide (WC) grains in a binder matrix of tough cobalt metal, using the liquid phase sintering process. The combination of WC and metallic cobalt as a binder is a well-modified system not only relating to its properties, but also to its sintering behavior. At high temperatures, WC is highly soluble in cobalt and the liquid cobalt binder also enables excellent wetting of WC. These properties lead to excellent densification during liquid phase sintering, and in a pore-free structure. Due to this reason, a material that integrates toughness, high strength, and excellent hardness are obtained. History The production of tungsten carbide can be traced back to the early 1920s when the German electrical bulb company, Osram, looked for substitutes to the costly diamond drawing dies used in the manufacture of tungsten wire. These efforts led to the invention of cemented carbide, which was soon manufactured and marketed by numerous companies for several applications, where its high wear resistance was especially crucial. The first tungsten carbide-cobalt grades were soon effectively applied in the cutting and milling of cast iron. In the early 1930s, pioneering cemented carbide companies introduced the first steel-milling grades which, besides cobalt and tungsten carbide, also contained carbides of tantalum and titanium.