Research of titanium powder obtained by SHS–hydrogenation and dehydrogenation in a vacuum furnace

Abstract

The method of SHS (self-propagating high-temperature synthesis) allows the efficient synthesis of titanium hydride. The article presents new results of experimental studies of titanium powders synthesized by the method of SHS hydrogenation and dehydrogenation in a vacuum furnace. Changes in the microstructure, phase and chemical composition during hydrogenation-dehydrogenation of a titanium sponge were studied. The titanium sponge was hydrogenated in a high-pressure SHS reactor at a hydrogen pressure of 3 MPa. The content of oxygen and carbon impurities decrease in the process of SHS hydrogenation was found. After hydrogenation, the sponge is a single-phase δ-hydride of titanium with a tetragonal lattice, the particles have a fragmentary shape. In the obtained titanium hydride, an increased hydrogen content of 4.64 wt. % was noted. The hydrogenated titanium sponge was mechanically crushed in a drum-ball mill to a particle size of 40 – 250 microns. Dehydrogenation of titanium hydride powder was carried out in a vacuum furnace at a temperature of 850 °C for 220 minutes. Titanium after dehydrogenation is a single-phase α-titanium powder with a hexagonal close packed lattice, the size and shape of the particles have not changed. The technological process under study provides the possibility of obtaining high-quality titanium powders of the necessary granulometric composition for various fields of powder metallurgy.