金属注射成形Ti-6Al-4V烧结坯的力学性能与烧结时间关系

研究了在1260℃烧结时,烧结时间对Ti-6Al-4V烧结坯力学性能的影响.结果表明平均晶粒尺寸为45 μm的氢化-脱氢粉末样品在1 260C烧结3 h～6 h,其相对密度为95.6%～96.7%、拉伸强度648 MPa～686 MPa、屈服强度526 MPa～615 MPa,但延伸率仅小于4%.90%气雾化(晶粒尺寸为32.5 μm)和10%氢化-脱氢混合粉末样品在1 260℃烧结2 h～6 h,其相对密度大于95%、拉伸强度800 MPa～848 MPa、屈服强度712 MPa～762 MPa、延伸率7.4%～9.5%.混合粉末样品的力学性能几乎达到美国ASTM粉末冶金的标准.

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(average particles 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.