【作者】 俞宇颖； 谭华； 朱建士； 胡建波； 陈大年； 戴诚达；

【Author】 YU-Yuying TAN Hua, ZHU Jianshi,,HU Jianbo,CHEN Danian, DAI Chengda (Laboratory for shock Wave and Detonation Physics Research,Southwest Institute of Fluid Physics,Mianyang Sichuan, 621900 Beijing Institute of Applied Physics and Computational Mathematics, Beijing, 100088 Centers of Mechanics and Material Sciences, Ningbo Univercity, Ningbo Zhejiang 315211)

【机构】 中国工程物理研究院流体物理研究所冲击波物理与爆轰物理实验室； 北京应用物理与计算数学研究所； 宁波大学力学与材料科学研究中心；

【摘要】 本文由实验结果出发,简要阐述了金属从冲击压缩状态卸载时的准弹性卸载特性及其可能的物理机制。在此基础上给出了强冲击载荷作用下准弹性卸载特性的表达方式--有效剪切模量及其实验测量方法。根据本文测量的 LY12铝在20-70GPa冲击压缩下的高压声速数据,计算了它的有效剪切模量,并与冲击动力学中广泛使用的SCG本构模型的计算结果进行比较。结果表明:SCG本构模型不能用于描写准弹性卸载行为:而用有效剪切模量计算的卸载波剖面能够很好地再现实验测量结果。说明需要用新的本构方程对准弹性卸载过程进行描述。更多还原

【Abstract】 The quasi-elastic release behavior and the possible intrinsic mechanisms for metal materials released from strong shock-compressions were described briefly. Based on the experimental observations and the analyses of this study, we delineated in this paper how to use the effective shear modulus to express the main features of the quasi-elastic release behavior and to determine the shear modulus experimentally. Effective shear moduli were calculated based on the measured sound velocities of LY12 aluminum under shock loadings from 20-70GPa. Comparisons with the Steinberg-Cochran-Guinan constitutive model show that this widely used constitutive model could not describe correctly the quasi-elastic release behavior for LY12 aluminum subjected to strong shock-loadings. Calculations by using our effective moduli to reproduce the release wave profiles have excellent agreements with the experiment record, implying that new constitutive equation should be developed for depicting the quasi-elastic release process.更多还原