中文摘要：

采用任意反射面速度干涉系统，通过对窗口碰撞面做特殊防护处理，发展了反向加载测量高压卸载声速的实验技术，解决了以往因使用缓冲层而不能得到样品材料体积声速的局限．利用该方法测量了Sn样品在37-80GPa压力范围内的高压卸载声速，得到了较高精度的声速测量结果（纵波声速测量误差约为2％，体积声速误差约为5％），且与热力学理论计算结果一致．

英文摘要：

In this paper, reverse-impact method for measuring release sound velocities was improved through special treatment of the impacted face of the window, and using time-resolved velocity interferometer system for any reflector. Our experimental technique solved the problem that bulk and longitudinal sound velocities can not be obtained simultaneously using the original method reported in the literature, due to the effect of release behaviors in the buffer. With the modified reverse-impact method, sound velocities of tin were measured with higher accuracy （measuring errors of longitudinal and bulk sound velocities being about 2% and 5%, respectively） in the range of 37-80 GPa. The experimental results are consistent with thermodynamic theoretical values.