微型正挤压尺度效应实验研究

为研究晶粒尺寸对微型正挤压工艺的影响,设计了微成形实验,在常温下对具有不同晶粒尺寸的微型铜圆柱体坯料进行了微型正挤压成形,获得了微小尺度下材料流动的特点及相关实验参数。所得实验结果表明,随着晶粒尺寸的增大,成形实验的可重复性变差,即材料出现非均匀流动;凸模的单位压力逐渐减小,但是成形过程中成形力变化趋势并不随晶粒尺寸的变化而变化。

Research on microforming by extrusion test

In order to study the influence of grain dimension on microforming process,at room temperature,micro forward extrusion process with micro copper cylinders which have different grain size were proceeded,and the characteristics of materialflow in micro dimension as well as relevant processing parameters were obtained.The results indicate that,with the increase of grain size,the repeatability of the extrusion test under the same kind of conditions becomes inconsistent,due to the occurrence of heterogeneous flow of material;the unit pressure of upper die decreases with the increase of grain size,while the change of grain dimension has less influence on the tendency of forming load at different forming stage.