固溶时效处理对高强高韧钛合金显微组织与力学性能的影响

对固溶时效处理后的高强高韧钛合金初生α相的体积分数、尺寸,次生α相的体积分数和α_s/β相界面密度等显微组织特征进行了定量表征和统计分析,探讨了随着固溶温度的变化,高强高韧钛合金显微组织与其力学性能间的相关性.结果表明:在α+β两相区固溶时效处理,随着固溶温度的升高,合金初生α相的体积分数降低,相尺寸先降低后略有升高,次生α相的体积分数升高,α_s/β相界面密度先升高后降低.初生α相的体积分数与伸长率、静力韧度和裂纹形成功正相关,α_s/β相界面密度与合金屈服强度成正相关. 

Effects of solution-aging treatment on microstructure and mechanical properties of a high-strength and high-toughness titanium alloy

Solution-aging treatment was performed to a high-strength and high-toughness titanium alloy. Several microstructural feature including volume fraction of primary α phase, size factor of primary α phase, volume fraction of secondary α phase, α_s/β interface density, were quantitatively characterized. By making a statistical analysis of the microstructure characteristics, the relationship between microstructure features and mechanical properties of the high-strength and high-toughness titanium alloy was investigated as solution temperature changed. The results show that with the increase of solution temperature in α+β phase, the volume fraction of primary α phase decreases, the size factor of primary α phase firstly decreases and then increases, volume fraction of secondary α phase increases, and the α_s/β interface density increases and then decreases. The elongation, static toughness and crack initiation energy increase with the growth of the volume fraction of primary α phase. And yield strength is positively correlated with the α_s/β interface density.