固溶时效工艺参数对TA19钛合金显微组织与拉伸性能的影响

对TA19钛合金进行不同温度(930,960,990℃)固溶2h+不同温度(550,590,630℃)时效8,16h热处理,研究了工艺参数对显微组织与拉伸性能的影响。结果表明:不同温度固溶+590℃时效8h处理后,随着固溶温度的升高,试验合金中的等轴α相含量降低,抗拉强度增大。经960℃固溶2h处理后,试验合金的组织由等轴α相和α′马氏体组成,在后续550℃时效8h过程中,α′马氏体分解不充分,颗粒状α相含量较少,合金抗拉强度增加有限;当时效温度升高到590℃,时效时间分别为8,16h时,组织中析出细小弥散的颗粒状α相,抗拉强度提高;继续升高时效温度至630℃时,α相粗化,抗拉强度又有所下降。

Effect of Solid Solution and Aging Process Parameters on Microstructure and Tensile Property of TA19 Titanium Alloy

TA19 titanium alloy was treated by solid solution at different temperatures(930,960,990℃)for2 hand then aging at different temperatures(550,590,630 ℃)for 8,16 h.Effects of process parameters on microstructure and tensile property were studied.The results show that after solid solution at different temperatures and then aging at 590℃for 8 h,the equiaxedαphase content in the test alloy decreased and the tensile strength was improved with the rise of solid solution temperature.After solid solution at 960℃for 2 h,the microstructure of the test alloy was composed of equiaxedαphase andα′martensite.During the subsequent aging at 550 ℃for 8 h,α′martensite decomposed unsufficiently,so the content of granularαphase was relatively small and therefore the tensile strength of the alloy increased limitedly.When the aging temperature rose to 590℃ and the aging time was8 hand 16 h,fine and diffuse granularαphase precipitated in the microstructure,resulting in the increase of tensile strength.When the aging temperature continuously increased to 630 ℃,theαphase was coarsened and the tensile strength decreased.