Abstract
In this study, we focused on the sintering performance of SP-700 (Ti-4.5Al-3V-2Mo-2Fe) and mechanical properties of SP-700 reinforced with titanium boride (TiB/SP-700) fabricated by spark plasma sintering (SPS). TiB whiskers formed in titanium by a solid-state reaction of titanium and TiB2 particles were analyzed with scanning electron microscopy and X-ray diffraction. The TiB/SP-700 was sintered at temperatures of 1073, 1173, and 1273 K and a pressure of 70 MPa for 10, 30, and 50 min. The volume fraction of TiB ranged from 1.7 vol% to 19.9 vol%. Tensile tests of TiB/SP-700 were conducted at room temperature, and the effect of TiB volume fraction on the tensile properties of TiB/SP-700 was investigated. The TiB/SP-700 (5.0 vol%) sintered under all conditions had a relative density of over 99.0 vol%. The TiB was perfectly formed from TiB2 particles in SP-700 by SPS under all sintering conditions. In addition, the TiB/SP-700 sintered at 1173 K for 10 min had the maximum tensile strength of 1193 MPa. At all sintering durations, the tensile strengths of TiB/SP-700 decreased at 1273 K.
