中文摘要：

以TC4钛合金激光立体成形件及锻件为研究对象，采用不同热处理制度对TC4 钛合金激光立体成形件进行处理得到不同的热处理组织，并采用超声波无损检测方式获得超声波纵波声速和衰减系数，明晰超声参量和显微组织的相互作用机理。结果表明，不同的显微组织具有不同的超声波纵波声速和衰减系数；相比超声波纵波声速而言，衰减系数对TC4钛合金激光立体成形显微组织的变化更为灵敏。

英文摘要：

Laser solid forming （LSF） TC4 alloys and forging TC4 titanium alloy are studied. LSF-TC4 alloys are processed by different heat treatments to get different heat treatment microstructures. In order to figure out the relationship between ultrasonic parameters and microstructures, ultrasonic nondestructive testing is taken on these alloys to get ultrasonic longitudinal wave velocity and attenuation coefficient. The results show that samples with different microstructures have different velocities and attenuation coefficients. Compared with longitudinal wave velocity, attenuation coefficient is more sensitive to the change of microstructure of laser solid forming alloys.