烧结工艺对TA15粉末冶金钛合金组织与性能的影响

Effect of sintering process on microstructure and properties of powder metallurgy TA15 titanium alloy

采用氢化脱氢TA15钛合金粉末为原料,通过模压成形与真空烧结及进一步热等静压(hot isostatic pressing,HIP)处理,制备TA15钛合金,对烧结合金及其热等静压后的组织形貌与拉伸性能进行分析与测试,研究成形压力及烧结温度对该合金组织与性能的影响。结果表明,随压制压力增大或烧结温度升高,烧结体的抗拉强度和伸长率都提高。热等静压后晶粒趋于球化,抗拉强度提升不明显,伸长率提升较显著。压制压力为700 MPa,烧结温度为1 300℃时,烧结合金的抗拉强度和伸长率都达到最大值,分别为1 050 MPa和2.81%。经HIP处理后合金的抗拉强度最高达到1 170 MPa,最大伸长率为5.6%。

TA15 titanium alloy was prepared by die forming and vacuum sintering and further treatment by hot isostatic pressing using TA15 alloy powder as raw materials. The microstructure and tensile properties of sintered alloy were analyzed and tested before and after HIP （hot isostatic pressing） treatment. The effects of forming pressure and sintering temperature on the microstructure and tensile properties of the alloy were studied. The results show that： the tensile strength and elongation of the sintered body increase with increasing the compacting pressure and sintering temperature. The grains tend to be sphericity after HIP treatment, the elongation of the sintered body increases obviously but the tensile strength increases slightly. The maximum tensile strength of 1 050 MPa and elongation of 2.81% can be obtained under the compacting pressure of 700 MPa and sintering temperature of 1300℃. The TA15 titanium alloy with the tensile strength of I 170 MPa and elongation of 5.6% is obtained after HIP treatment.