45钢柱壳膨胀断裂的应变率效应

Strain-rate effects of expanding fracture of 45 steel cylinder shells driven by detonation

采用前照明高速分幅照相技术拍摄到在爆轰加载下45钢柱壳表面裂纹生成、扩展及产物泄漏过程的清晰图像,较准确地测量了膨胀断裂的时间与应变。45钢柱壳在炸药爆轰加载下,断裂应变随应变率的增加而增加,当应变率达到一定值,断裂应变随应变率的增加而降低,出现了动态断裂中的塑性峰现象。

The high-speed photography was applied to observe the expanding fracture of 45 steel cylinder shells driven by detonation. The clear photos of expanding process of steel cylinder shells were obtained. The fracture strains of the expanding steel shells increase with the strain-rate, and decrease when the straln-rate arrived at a certain constant. The plasticity peak during dynamic fracture was experimentally observed. The strain-rate according to the peak of fracture strain is around 7.1 × 10^4 s^-1.