Effect of titanium on the as-cast microstructure and impact toughness of hypereutectic high-chromium cast iron

Abstract The effect of titanium on the as-cast microstructure of a hypereutectic high-chromium cast iron was investigated by means of optical microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The results indicate that the primary M 7C3 carbides are refined and spheroidized with the addition of a suitable amount of titanium. TiC is found in the primary carbide by energy dispersive spectroscopy analysis. The mechanism of titanium modification on the microstructure of the alloy is also discussed. In addition, the impact test result indicates that, compared with the hypereutectic high-chromium cast iron without titanium addition, the impact toughness value of hypereutectic high-chromium cast iron with titanium additions is improved and approximately reaches 6.4 J · cm−2.