T8, T10 and T12 are carbon tool steels. They are very hard. The Brinell hardness in annealed state is more than 300.Manual saw blade is T12 material, just quenching, hardness is greater.10 and 20 are low carbon, high quality structural steel, very soft, Brinell hardness is less than 155.Therefore, the fitter saw, laborious, the saw is very easy to wear.

Tool steels are high quality steels developed with controlled chemical composition to form properties essential for working and shaping of other materials. They are normally delivered to the suppliers in the soft annealed condition, which makes it easy for the manufacturer to machine the material with cutting tool for different applications.AISI T8 tool steel is a tungsten-cobalt-vanadium high-speed tool steel. The following datasheet will provide an overview of grade T8 tool steels.