The strength and deformation mechanisms in magnesium can be significantly affected by anisotropy, high strain rates, and pressure. In this study, pressure shear plate impact (PSPI) experiments are conducted to measure the strength of extruded polycrystalline magnesium at pressures varying from 5 to 10 GPa at a nominal strain rate of 10⁵ s⁻¹. The experimental technique enables to first shock load the material sample to the desired normal stress in one direction, and then shear the material in a perpendicular direction. A recently developed hybrid analysis method for PSPI experiments is used to extract the stress–strain curves of magnesium from the particle velocity records measured at the rear surface of the target. The PSPI experimental results reveal a slower twinning saturation at high pressures. To better understand the material behavior under the combined stress states in the PSPI experiments, the results were compared with that of a specimen deformed by a two-step process of quasi-static compression followed by dynamic shear loading at relatively low pressure. The two-stage loading at low pressure, and the calculation of temperature rise in the PSPI experiment revealed that the combined effect of the reorientation and the temperature rise lower the flow strength of magnesium at high pressures under multiaxial loading.

镁的强度和变形机制会受到各向异性，高应变速率和压力的显着影响。在这项研究中，进行了压力剪切板冲击（PSPI）实验，以测量在5至10 GPa的压力下，标称应变率为10 ⁵ s ^-1的挤出多晶镁的强度。。实验技术能够首先在一个方向上将材料样品冲击加载到所需的法向应力，然后在垂直方向上剪切材料。最近开发的用于PSPI实验的混合分析方法用于从在靶材后表面测得的粒子速度记录中提取镁的应力-应变曲线。PSPI实验结果表明，在高压下孪晶饱和速度较慢。为了更好地了解PSPI实验在组合应力状态下的材料行为，将结果与通过准静态压缩的两步过程然后在较低压力下进行动态剪切加载而变形的样品的结果进行了比较。低压两阶段加载