纯钒在冲击加载下的动态拉伸断裂和弹性波衰减特性  

Dynamic tensile fracture and the decay of elastic precursor wave in shocked pure vanadium

作　　者：李雪梅[1] 俞宇颖[1] 胡昌明[1] 张祖根[1] 彭建祥[1] 王为[1] LI Xuemei;YU Yuying;HU Changming;ZHANG Zugen;PENG Jianxiang;WANG Wei(Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics,China Academy of Engineering Physics, Mianyang 621999, Sichuan, China)

机构地区：[1]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重点实验室,四川绵阳621999

出　　处：《爆炸与冲击》2019年第1期30-35,共6页Explosion and Shock Waves

摘　　要：利用平板撞击和激光干涉测速技术,实验研究了国产热等静压纯钒在压力5.2～9.0 GPa、拉伸应变率0.47×10~5～1.19×10~5s^(-1)冲击加载下的层裂特性。结果表明:国产热等静压纯钒具有较强的抗动态拉伸断裂能力,其层裂强度在4.0～5.3 GPa范围,明显高于相似加载条件下文献给出的熔炼钒结果,这主要与热等静压加工工艺下纯钒杂质含量更低、内缺陷更少有关;同时,纯钒层裂强度对冲击压力和拉伸应变率均比较敏感。此外,对弹塑性加载速度剖面的分析发现:在6 mm样品厚度范围,纯钒的弹性波幅值随样品厚度增大而减小,雨贡纽弹性极限随样品厚度的衰减规律较好地满足指数关系σ_(HEL)=3.246 (h_s/h_0)^(-0.386),h_0为单位长度。By using plate impact and velocity interferometry,the dynamic tensile fracture(spall)of shocked pure vanadium was studied in the pressure range of5.2-9.0GPa,where the average tensile strain rate was in the range of0.47×105-1.19×105s-1.All the vanadium samples used here were made by the hot isostatic pressing(HIP)method.Our results show that the HIP vanadium has a higher spall strength than those given in literatures,which lies in the range of4.0-5.3GPa,and increases with both the shock pressure and tensile strain rate.The higher spall strength of the HIP vanadium can be ascribed to the higher purity and fewer initial defects in material than those made by the remelting method.Additionally,the analysis on elastic precursor wave in vanadium indicates a power decay of Hugoniot elastic limit(σHEL)with the dimensionless thickness of the sample(h s/h0),where h0is a unit length.The coefficient and exponent of the power function best fitting the experimental data are3.246and-0.386,respectively,when the vanadium sample’s thickness h s is no greater than6mm.

关 键 词：纯钒 层裂强度 弹性前驱波衰减 热等静压 拉伸断裂 

分 类 号：O382.3[理学—流体力学]