Effect of mechanical and electrical activation on the combustion synthesis of Al3Ti

Abstract

Titanium aluminides have attracted immense interest as lightweight intermetallic compounds that pos- sess good high-temperature mechanical and corrosion properties. In the present work, titanium aluminides (Al3Ti) have been reactively processed from elemental powder using a combined mechanical and electrical activation approach. The effect of mechanical activation and electric current intensity on the ignition and phase development is discussed. Ignition was not possible when powders were milled for a short time, while prolonged milling resulted in mechanical activation that promoted a self-propagating- type reaction. The time to engulfment of the compact with the reaction wave was found to decrease with an increase in current intensity. A secondary reaction occurred at the higher current intensity, which in turn increased the prod- uct homogeneity.