High-speed steels (SS, HSS)

High-speed steels are high-alloy steels. Important alloying elements are:

Tungsten and vanadium: they increase the hot hardness
Chrome: Chrome causes an increase in through hardening
Molybdenum: Molybdenum ensures high toughness and higher through hardenability
Cobalt: The addition of cobalt increases the tempering resistance and increases the hot hardness

High-speed steels achieve a hot hardness of up to 600°C and cutting speeds of up to 60 m/min.

An increase in tool life can be achieved by hard chromium plating, carbonizing, nitriding or titanium carbide coating.