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℃) for 2 h and 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 equiaxed α phase 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 equiaxed α phase and α' martensite. During the subsequent aging at 550℃ for 8 h, α' martensite decomposed unsufficiently, so the content of granular α phase was relatively small and therefore the tensile strength of the alloy increased limitedly. When the aging temperature rose to 590℃ and the aging time was 8 h and 16 h, fine and diffuse granular α phase precipitated in the microstructure, resulting in the increase of tensile strength. When the aging temperature continuously increased to 630℃, the α phase was coarsened and the tensile strength decreased.