Before 1879, most of the industrialised countries were only familiar with high-carbon steel forged tools containing about 1% carbon and 0.2% managanese.
In 1900. F.W. Taylor and M. White developed HSS giving a cutting speed of 60 fpm.
in 1920, Germans introduced tungsten carbide.
In 1941, German develop an alternative to tungsten carbide and developed ceramic (oxide) tools material.
Cutting speeds were increased steadily in the machining processes due to various researches. Presently highest cutting speeds are obtained with polycrystalline Diamond tools. 1800 metres per minute are obtained in typical applications. Even 2100 metres/min was possible with free machining and nonferrous materials.
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