平面冲击下铜的拉伸应变率相关特性研究

本文对冲击加载下高纯无氧铜的拉伸应变率相关特性进行了实验研究.实验中利用磁测速系统测试撞击前飞片速度,利用光纤位移仪——多普勒探针系统测试样品自由面粒子速度剖面.对自由面速度剖面的特征参量进行计算分析,结果表明:铜样品的层裂强度随着拉伸应变率的增加而增加,对比发现层裂强度不仅受加载条件的影响,同时受到材料本身微细观结构影响;同时随着拉伸应变率的增加,自由面速度的回跳斜率呈现出先缓慢增加后迅速增加的临界特性;最后,通过层裂样品中波系相互作用,给出了自由面速度回跳过程中的振荡特征随着拉伸应变率增加而逐渐消失的物理过程.

Rate-dep endent characteristics of copp er under plate impact

In this paper, the rate-dependent characteristics of oxygen-free high-purity copper (OFHC) under plate-impact loading is investigated experimentally. The velocity of flyers is measured by magnetic measurement system, and the free surface velocity of targets is measured by Doppler pins system (DPS). Characteristic parameters of free surface velocity are calculated using the measured data. Results show that the spall strength of OFHC is enhanced with the increase in strain rate. It is indicated that the rate from the minima to the spall peak grows slowly at low stain rate, but steeply at high strain rate. The slope as it appears, from the minima to the spall peak is very different as the strain rate increases, The interaction of shock waves in the copper samples is systematically analysed to access the slope characteristics.
Keywords： oxygen-free high-purity copper spall free surface velocity rate-dependent characteristics