Cemented carbides are so named because they are composed principally of carbon mixed with other elements. The two types of cemented carbides are the tungsten and titanium tungsten varieties.
The tungsten type cemented carbides are less brittle than titanium-tungsten type. They contain 92-98% tungsten carbide and 2-8% cobalt. These cemented carbides are designed for machining brittle metals such as cast iron, bronze. They may also be used for steels.
The titanium-tungsten type are more wear resistant They contain 66-85% tungsten carbide, 5-30% titanium carbide and 4-10% cobalt. These cemented carbides are designed for machining tougher materials chiefly for various steels.
Cemented carbides are used as inserts brazed or screwed at the end of commercial steel tool holders. Cemented carbide tipped tools can machine metals at cutting speed 6 times more than that of HSS. However, it is very brittle, has low resistance to shock, and must be very rigidly supported to prevent cracking.
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