金属铍的压缩变形行为

利用材料试验机及Hopkinson杆装置系统开展热等静压金属铍在不同温度下的静动态压缩力学行为研究，获得了温度、应变率对金属铍屈服强度和加工硬化行为的影响规律。结果表明:金属铍在压缩应力状态下呈现出良好的塑性，同时其力学性能具有显著的应变率敏感性与热软化效应，屈服强度和流动应力随应变率提高呈明显增大趋势，随着温度升高逐渐降低。同时，室温下其加工硬化行为随着应变增大表现为分段硬化特征，随温度升高则趋于理想塑性。最后，采用修正的Johnson-Cook本构模型对实验结果进行了拟合，模型计算结果与实验结果吻合较好。

Compressive deformation behaviors of beryllium

The quasi-static and dynamic compression behavior of beryllium was investigated by using MTS and SHPB at different temperatures. Investigated results show that beryllium exhibits excellent plasticity under compression. Sensitive to the changes in temperature and strain rate, the yield point and flow stress of beryllium have an marked tendency to increase with the increase of the strain rate, and to decrease gradually with the rise of temperatures. At the same time, the work hardening behavior of beryllium exhibits a piecewise hardening feature as the strain increases at room temperature, and tends to become smooth as the temperature rises. Finally, a modified Johnson-Cook constitutive model was developed to predict the deformation behavior of beryllium over a wide range of temperatures and strain rates. The calculation results of the model are in good agreement with those achieved from the experiment.