爆炸膨胀环的截面尺寸效应

Size effects of expanding ring by explosive loading

利用爆炸膨胀环实验数据修正了无氧铜的J-C本构模型参数,计算获得的速度历史与实验测试结果吻合。通过数值模拟研究了膨胀环宽度对速度历史、应力状态的影响,发现:对厚度1mm的膨胀环,加载速度峰值随着膨胀环宽度的增加而增加,当宽度超过8mm后速度峰值不再变化;膨胀环宽度不超过2mm时,能较好满足1维应力状态的假定。膨胀环的应力状态在一定范围内具有明显的尺寸效应,可为爆炸膨胀环的试样尺寸设计提供参考。

The parameters of Johnson-Cook model were modified for OFHC copper by the data of ex- panding ring experiment. The numerical velocity of ring is consistent with the experimental result. With the width of ring increasing under 8 mm, the peak value of velocity increases. However, while the width is over 8 mm,the peak value of velocity arrives at a constant, but the slope of velocity varies with the width of ring. While the width of ring is twice of thickness, the stress state in expanding ring satisfies the one-dimensional stress assunption. The research shows that the stress state in expanding ring is influenced by the size of ring while explosive loading.