高应变率压缩加载下LY12铝圆管的剪切断裂研究

 通过回收破片的断口观察和金相分析研究了LY12铝圆管在高应变率压缩过程中的剪切断裂现象；回收破片具有典型的剪切断裂特征，断口与径向近似成45°夹角，断口观察发现断口面经历过径向摩擦；破片金相分析表明，绝热剪切带和裂纹首先在圆管内壁附近产生，然后沿最大剪应力线向外壁扩展。利用数值计算给出了圆管在内爆压缩加载下管壁内微元的应力、应变历史，为分析LY12铝圆管的剪切断裂提供了参考。

Shear Fractures of LY12 Aluminum Cylinder under High-Strain-Rate Implosive Loading

In this paper,the shear fracture performances of LY12 aluminum cylinder were studied under explosive loading.The recovered fragments showed shear characteristics. The fracture surface formed along the maximum shear stress curves.SEM images of the recovered fragments illustrate that the fracture surfaces have undergone friction.The adiabatic shear bands and microcracks all initiate near the inside wall and develop along the maximum shear stress curves to the outside wall of the cylinder.The histories of stress and strain from numerical calculations indicate the adiabatic shear bands initiate more easily near the inside of cylinder than in other zones,which corresponds to the results of metallographic analysis.