High Speed Steel (H.S.S)


It is the name given to the most common tool steel. As the name implies, it can cut steel
at high cutting speeds. These steels are high in alloy content, have excellent hardenability,
maintain their hardness at elevated temperatures around 650°C, are quite resistant to
wear and contain relatively large amounts of tungsten or molybdenum, together with
chromium, cobalt or vanadium. They are used to produce cutting tools to be operated
for various machining operations such as turning, drilling, milling, etc. A typical
composition of H.S.S. is tungsten 18%, chromium 4% and vanadium 1%, carbon 0.75 to
0.9% and rest iron.

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