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Why Is Cemented Carbide So Hard?

Cemented carbide is mainly composed of tungsten carbide and cobalt. Tungsten carbide (WC) is a metal ceramic with a Vickers hardness of up to 2200 HV, close to the 10000 HV of diamond. Its crystal structure is hexagonal, and carbon atoms and tungsten atoms are bonded by strong covalent bonds with a bond energy of up to 700 kJ/mol, giving it extremely high hardness. Cobalt is used as a binder, and the content is usually 6%-15%. Through powder metallurgy, tungsten carbide particles are firmly bonded at 1400°C high temperature sintering, and the gaps between particles are filled to form a composite material with high hardness, high density and toughness!

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