针对自洽强度方法存在的冲击加载-再加载的难题,提出了一种采用较高硬度材料为支撑制作组合飞片的简便方法。利用该方法获得了铝、锡和锆基金属玻璃较理想的冲击加载-再加载粒子速度剖面,验证了该方法的有效性。由本文获得的冲击加载-再加载粒子速度剖面,并根据自洽方法,计算得到了铝、锡和锆基金属玻璃再加载过程剪应力变化数据。进一步分析表明,在本文涉及的压力范围内,仅由冲击加载-卸载实验得到的铝、锡和锆基金属玻璃屈服强度将比实际结果降低20%~50%。因此,在采用自洽方法计算高压强度时,冲击加载-再加载数据不可或缺。
A convenient method for fabricating a layered impactor with a sample backed up by high hardness materials was developed to overcome the obstacle of the shock-reload experiments in the self-consistent yield strength technique. This method was validated by a series of ideal shock-reload particle velocities of aluminum,tin,and Zr-based bulk metallic glass obtained from the reverse-impact experiments at the peak shock stresses from 28 GPa to 48 GPa. The sum of the shear stresses for these materials in the reload process from the shocked state was estimated,and compared with the previously reported data in the release process. It is shown that the yield strength under a high pressure for the materials investigated will underestimate 20%-50%if without the reload data. Thus,shock-reload experiments are essential for the self-consistent yield strength method.