外部爆轰加载过程中金属圆管断裂实验研究

利用脉冲X光照相技术和高速摄影对HR 2抗氢钢圆管在外部爆轰加载下的压缩过程进行了动态诊断。X光照相观察到抗氢钢圆管在压缩过程中管壁内出现了宏观裂纹 ,回收破片具有显著的剪切断裂特征 ,金相分析观察到了绝热剪切带及微孔洞与微裂纹。对半圆管结构的压缩过程进行了高速摄影 ,直接观测到抗氢钢圆管内壁裂纹萌生与发展的动态过程。由两种动态诊断实验结果对比分析推断 ,抗氢钢圆管在外部爆轰加载压缩过程中 ,裂纹首先在圆管内壁生成。

Studies on the Fracture of Steel Cycinder under External Explosive Loading

The fracture phenomena of HR 2 steel cylinder under external explosive loading are studied by the dynamical technology of X flash photography and high speed photography. The results of X flash photography show that the fracture has occurred in the steel cylinder wall during the external explosive loading. There are clear shear characteristics on the collected fragments. The metallography examinations show that there are adiabatic shear bands on the tip of the microcracks and microvoids within the adiabatic shear bands. The germination and development processes of cracks have been directly observed by the high speed photography experiments. The comparison between the two kinds of experimental results shows that the cracks germinate firstly in the internal surface of steel cylinder, which agree with the quasi static stress analysis.