Hard metal is almost as hard as diamond. Hard metal has wide use in the mechanical industry for metal work — drilling, cutting and milling. Hard metal is manufactured in a complex industrial process. A fine powder including approximately 90% tungsten carbide and 10% cobalt plus small amounts of titanium, niob, tantal, molybdenum, sometimes 2–3% nickel and polyethylene glycol is pressed in a form. This results in a brittle black piece of a desired shape, which can be broken by hand force and which is easily finished or formed by grinding.
KeywordsContact Dermatitis Hard Metal Sodium Tungstate Hand Eczema Irritant Contact Dermatitis
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