The investigation of titanium hydride oxidation process

The process of titanium hydride oxidation was investigated by several methods. The results of TiHx thermal oxidation investigation show that it is the presence of hydrogen in hydride phases which influence the dynamics of titanium hydride oxidation (Ti-x-->TiHx-yOz-->Ti2O-->TiO2). Unfortunately the heating of titanium hydride in air results in sample caking. Hence it is impossible to obtain the pure titanium dioxide by using this method. The oxidation of titanium hydride in the low temperature oxygen plasma of microwave and glow discharges was also investigated. It is shown that the process of titanium hydride oxidation in O2-plasma of a glow discharge continues step-by-step and as in the case of thermal TiHx oxidation is also accompanied by sample caking. The efficiency of the oxidation process depends on the temperature and the time of treatment. The action of a low temperature oxygen plasma of microwave discharge upon titanium hydride didn't cause sample caking and led to rutile formation. The probable reasons why TiHx effectively oxidizes solely to rutile in a microwave discharge are discussed. (C) 1997 Elsevier Science S.A.