中文摘要：

使用扫描电子显微镜,分别对不同成形方式下（拉伸实验试样、冷冲压拉深试样及渐进成形试样）冷轧板断口形貌进行观察和分析.结果表明：与其他2种方法相比,渐进成形技术能充分发挥冷轧板的塑性变形能力;试样断口存在大量较深的韧窝,并在三向应力作用下被拉长;韧窝在工具头的不断推挤以及逐层碾压下,会进一步伸长并产生扭转;韧窝有较长的撕裂棱,断裂前发生较大的塑性变形.

英文摘要：

Using scanning electron microscope （SEM）, the fracture morphology of three kinds of specimen including tensile test, cold stamping drawing and incremental forming were analysed respectively. It was found that, compared with the other two methods, incremental forming can exert the ability of plastic deformation fully. There are plenty of dimples in specimen fractures, which were stretched under tri-axial stress. Because of the on-going pushing and graded grinding by tool head, the dimples were stretched further and twisted; and the dimples have longer tearing ridges, which reflect larger plastic forming before fracture.