Effects of carbon on microstructures and properties of high vanadium high-speed steel

The effects of carbon content on the microstructures, mechanical properties and wear behavior of high vanadium (10%) high speed steel were studied systemically. The results show that the carbides in high vanadium high speed steel are composed of the vanadium carbide, small amount of Cr composite carbide and Mo composite carbide. With the increase of the carbon content, the amount of carbides increases obviously, the shape of carbides is changed from rod, strip to bulk, spherical, and the microstructures of metallic matrix are transformed from the ferrite, the mixture of ferrite, the martensite and retained austenite to the martensite and retained austenite. The hardness and the wear resistance of high vanadium high speed steel are increased, but its impact toughness would be decreased.