固溶加时效处理对Gr.36钛合金棒材组织及性能的影响

摘要

The effect of solution and aging treatment on microstructure and properties of Gr.36 titanium alloy bars were studied in this paper.The microstructure, microhardness and tensile properties were evaluated.The results indicate that the solid solution effect is more sufficient in case of 750 ℃×1 h/AC than that of 650 ℃ and 680 ℃.The grain is completely recrystallization and α phase fully dissolves into β phase.The aging treatment is excuted after treated at 750 ℃×1 h/AC.The microhardness is relatively low (1 460 MPa to 1 490 MPa) when aging at the temperature of 500 ℃ in different holding time.The microhardness (2 340 MPa to 2 690 MPa) increases by almost a fold when aging at the temperature of 450 ℃ for 16 h and becomes stable with growing the aging time.The tensile strength of the sample aging at 450 ℃ increase about 40% than that of aging at 500 ℃.Consequently, the second phase separate out sufficiently and the microstructure matches well with the mechanical properties when the heat treating regime is 50 ℃×1 h/AC+450 ℃×20 h/AC.%研究固溶及时效处理对Gr.36钛合金棒材组织及性能的影响,对金相组织、显微硬度及拉伸性能进行了表征.结果表明:与650、680 ℃相比,采用750 ℃×1 h/AC的固溶处理,棒材发生了完全再结晶,α相完全溶入β相中,固溶效果最充分;在相同固溶制度下(750 ℃×1 h/AC),当时效温度为500 ℃时,时效8~24 h后,试样显微硬度均较低,为1 360~1 490 MPa;当时效温度为450 ℃时,随着时效时间增加至16 h时,显微硬度提高了近一倍,达2 340~2 690 MPa,并随时效时间的继续增加而趋于平稳;与500 ℃相比,450 ℃时效20 h后棒材强度提高了近40%.经750 ℃×1 h/AC+450 ℃×20 h/AC的固溶及时效处理后,Gr.36钛合金棒材的第二相得到充分析出,显微组织与力学性能达到良好匹配,能够符合协议标准要求.