Abstract:The hydrogenation reaction of electrolyzed titanium, as the first step during hydrogenation-dehydrogenation for the preparation of titanium powder, was studied. The titanium hydride was prepared through the reaction between electrolyzed titanium and hydrogen at different hydrogenation temperatures and different time. The evolutions of hydrogen and oxygen contents, density, hardness and phase composition before and after hydrogenation were characterized under different hydrogenation conditions. The results show that the main phases of titanium hydride were TiH_1.924, TiH_1.971 and TiH₂. Increasing the hydrogenation temperature could not enhance the hydrogen content but increase the oxygen content. The effect of the hydrogenation time on the hydrogen content was not obvious. The optimal parameters of the hydrogenation process were obtained: heating at 400 °C and holding for 2 h, by which the hydrogen content of 3.63% and oxygen content of 0.18% (mass fraction) can be obtained. In addition, the microstructure, orientations and tissues of electrolyzed titanium and titanium hydride were detected.

Key words: titanium powder; hydrogenation reaction; molten salt electrolysis; hydrogen content