应变率对铸造镁合金AZ91压缩力学性能影响研究

Effect of Strain Rate on Compression Mechanical Properties of Cast Magnesium Alloy AZ91

利用INSTRON准静态试验机和分离式Hopkinson压杆系统对铸造镁合金AZ91进行了不同应变率下的压缩试验。试验结果表明:应变率对镁合金AZ91压缩性能影响很大。室温条件下,铸造镁合金AZ91具有明显的应变硬化性质。在准静态压缩过程中材料对应变率负敏感,当应变率达到7×103s-1时,AZ91表现出明显的应变率敏感性。

The compressive mechanical behavior of cast AZ91 was tested at a wide range of strain rates(10-3～104 s-1) by using INSTRON testing system and split Hopkinson pressure bar.The experimental results show that the deformation behaviors of cast AZ91 alloy are influenced strongly by the strain rates.AZ91 has obviously strain hardening character at room temperature and the mechanical behavior of cast AZ91 declines with the strain rate increasing at low strain rate(10-3～10-1 s-1).When the strain rate exceeds 7 000 s-1,AZ91 shows a strong strain rate sensitivity.