聚碳酸酯拉伸应变局部化实验

采用电子散斑技术对聚碳酸酯材料拉伸过程的表面变形进行了实验研究,量化得到了试验在拉伸载荷作用下的连续变形分布,用扫描电镜(SEM)观察了断口形貌.结果表明,在粘弹性区域,沿拉伸方向产生平行的形变带,离面位移随载荷之间而增大;在屈服区域,产生应变局部化,形成800μm的剪切带,而且聚碳酸酯的断裂是由局部应力集中所致,其裂...

Experiment of Strain Localization of Polycarbonate

The electronic speckle pattern interferometry(ESPI) technology was introduced into the study on the deformation of polycarbonate tensile sample surface.According to the experimental work,the quantitative results on the deformation of the process of the tensile were got.Fracture morphology was observed by scanning electron microscope(SEM).The experiment results indicate that parallel-deformation zone is produced on the viscoelastic region of stress history curve and out-of-plane displacement increases with load increasing;At the yield region,the phenomenon of strain localization becomes visible,shear band with the width of about 800 μm appears,fracture of polycarbonate is caused by local stress concentration,it′s controlled by the propagation speed of secondary crack,morphology of fracture surface shows characterization of parabola.