Microstructure and Properties of Porous Titanium Materials Fabricated by Cold Pressing and Low-Temperature Vacuum and Hydrogen Sintering

The effect of temperature and time parameters and sintering conditions on the structure and properties of porous VT1-0 titanium samples fabricated by cold pressing of rapidly quenched fibers is studied. The samples are sintered at 750-850 degrees C for 1.5-2 h in a vacuum and upon hydrogenation to a hydrogen concentration of 2.5 wt % and subsequent dehydrogenation. The hydrogenation allows us to fulfill the sintering of fibers in a temperature range corresponding to the beta-Ti + TiH2 phase region, and the nonhydrogenated fiber is sintered at the same temperatures corresponding to the alpha-Ti region. The hydrogenation-dehydrogenation in the course of sintering is found to exclude the imperfection of joint zones and to increase the mechanical properties of the porous sintered material. The maximum reached proportionality limit of the material subjected to hydrogen and vacuum sintering is 108 and 71 MPa, respectively.