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利用分离式霍普金森压杆研究了泡沫铝硅合金的动态压缩力学性能,得到了应变率为1400s-1~2500s-1的动态应力-应变曲线,且与准静态压缩实验结果进行了对比,分析了应变率对泡沫铝硅材料压缩强度和吸能特性的影响。动态压缩实验过程中,针对泡沫铝硅合金的低阻抗特点,采用LC4铝压杆和半导体应变片改进了测试装置和方法,保证了实验结果的可靠性。结果表明:应变率对泡沫铝硅合金的流动应力有着明显的影响,其流动应力随着应变率的增大而增大;由于惯性效应和胞孔的坍塌,在弹性极限处应力出现波动,且波动应力随应变率的增大而增大。该文还讨论了泡沫铝硅合金在不同应变率下的吸能效率。
Dynamic Hopkinson pressure bar was used to study the dynamic compressive mechanical properties of Al-Si foam. The dynamic stress-strain curves of strain rate of 1400s-1 ~ 2500s-1 were obtained and compared with the results of quasi-static compression experiments. The effect of strain rate on the compressive strength and energy absorption properties of aluminum-silicon foam materials was analyzed. In the process of dynamic compression experiment, aiming at the low impedance characteristic of Al-Si alloy, the testing device and method were improved by LC4 aluminum bar and semiconductor strain gauge, which ensured the reliability of experimental results. The results show that the strain rate has a significant effect on the flow stress of Al-Si foam and the flow stress increases with the increase of strain rate. Due to the inertia effect and cell collapse, the stress fluctuates at the elastic limit Wave stress increases with increasing strain rate. The article also discusses the energy absorption efficiency of foamed Al-Si alloys at different strain rates.