PMI泡沫材料动态压缩力学性能及吸能特性研究  

Investigation of the dynamic compression behavior and energy absorption properties of PMI foam

作　　者：李世杰[1] 杨晨 谭柱华 LI Shijie;YANG Chen;TAN Zhuhua(School of Mechanical Engineering,Hebei University of Technology,Tianjin 300401,China)

机构地区：[1]河北工业大学机械工程学院,天津300401

出　　处：《河北工业大学学报》2024年第6期52-60,共9页Journal of Hebei University of Technology

基　　金：国家自然科学基金资助项目(11672214)。

摘　　要：针对PMI泡沫材料的低阻抗特性,利用铝杆和半导体应变片改进了分离式霍普金森压杆(SHPB)装置的加载和测试方法,分析了撞击杆长度对实验结果的影响,发现撞击杆长度为800 mm时可保证实验结果的可靠性。利用改进的SHPB装置开展了不同密度PMI泡沫材料的动态压缩实验,得到了PMI泡沫材料在应变率为2150~3500 s^(-1)下的动态应力-应变曲线,分析了密度和应变率对PMI泡沫材料动态力学性能和吸能特性的影响。结果表明:高应变率下PMI泡沫材料的平台应力随应变率的增大有着显著的提高,与准静态相比,其平台应力最大提升了52.5%,其动态吸能效率也随着密度、应变率的增大而增大,表现出明显的应变率敏感性;基于密度为52 kg/m^(3)、75 kg/m^(3) PMI泡沫材料的动态实验结果,得到了以密度、应变、应变率等为参数的动态压缩本构方程,并与密度为110 kg/m^(3) PMI泡沫材料的实验结果进行了对比验证,两者吻合较好。该工作为PMI泡沫材料在冲击防护中的应用提供了参考。Due to the low impedance characteristics of PMI foam materials,aluminum rods and semiconductor strain gauges were used to improve the loading and measurement methods for the split Hopkinson pressure bar(SHPB),and the effect of the length of strike bar on the experimental results was analyzed.It is found that the strike bar with a length of 800 mm can ensure the reliability of the experimental results.The dynamic compressive experiments of PMI foam ma-terials with different densities were carried out by using the improved SHPB,and the dynamic stress-strain curves were obtained at strain rates ranging from 2150-3500 s^(-1),and the influence of the density and strain rate on the dynamic me-chanical properties and energy absorption characteristics of PMI foam materials was analyzed.The results show that the platform stress of PMI foam at high strain rate increases significantly with the strain rate.Compared with the results of the quasi-static load case,the platform stress increases by 52.5%,and the dynamic energy absorption efficiency also in-creases with density and strain rate.The PMI foam shows an obvious strain rate sensitivity.Based on the experimental re-sults of the density of 52 kg/m^(3),75 kg/m^(3) PMI foam materials,a revised constitutive model equation was developed that incorporates the parameters of density,strain and strain rate.Then,the revised constitutive model was then verified by using experimental data of the density of 110 kg/m^(3).The results are in good agreement.This work provides a data support for the application of PMI foam materials in the field of safe protection.

关 键 词：PMI泡沫材料 分离式霍普金森压杆 动态力学性能 高应变率 吸能效率 

分 类 号：TB383[一般工业技术—材料科学与工程]