Influence of Sintering Time on Mechanical Properties of Ti-6Al-4V Compacts by Metal Injection Molding

Ti-6Al-4V compacts were fabricated by metal injection molding (MIM). Influence of vacuum sintering time on mechanical properties of the sintered compacts at 1260℃were investigated. The experimental results show that the compacts sintered at 1 260℃ for 3 hours～6 hours, which was made from hydrogenation-dehydrogenation(HDH) powder(averageparticles size is 45 μm), had a relative density of 95.6%～ 96.7%, ultimate tensile strength (648 MPa～686 MPa) and 0.2% yield strength (526 MPa～615 MPa) but a lower elongation (<4%) and that the compacts sintered at 1 260℃ for 2 hours～6 hours, which was made from 90wt% gas-atomized powder(average particles size is 32.5 μm) and 10 wt% HDH powder, had higher relative density (>95%),ultimate tensile strength (800 MPa～848 MPa), 0.2% yield strength (712 MPa～762 MPa) and high elongation (7.4%～9.5%).The mechanical properties of mixed powder specimens were nearly equivalent to the ASTM for the PM compacts.