Effect of titanium on the structure and properties of cast molybdenum high-speed steel

Abstract

The possibility of alloying high-speed steel with a large amount of titanium was proposed in the 1940's, however for a long time it could not be realized in practice because of the difficulty in introducing titanium into the melt. In recent years interest in studying the effect of titanium on the structure and properties of highspeed steel has increased significantly as a result of the scarcity of tungsten and molybdenum. As a rule, titanium is added to tungsten and tungsten-molybdenum steels, and in order to bond titanium into TiC carbide, 0.2-0.25% C is added for each 1% Ti. Results are given in this work for determination of the effect of titanium on the structure and properties of cast tungsten-free high-speed steel type M6 containing 0.8% C, 3.6% Cr, 6.2% Mo, and 0.4-3.5% Ti. The amount of carbon in all the melts was the same, as a result of which the effect of secondary martensite transformation on secondary hardness and red hardness for the steel was excluded. Thus, it was possible to determine the effect of titanium alone on dispersion hardening of alpha-solid solution.