微小尺度镦挤复合成形研究

Study on micro scale extrusion forging process

为了研究晶粒尺寸对微成形工艺的影响,在常温下对具有不同晶粒尺寸微型铜圆柱体坯料进行了微型镦挤复合成形,获得了微小尺度下材料流动特点及相关工艺参数。所得结果表明,所成形的微型杆-法兰件挤出杆端随着材料晶粒尺寸的增大而逐渐呈现出凹凸不平的现象,即出现非均匀流动;随着晶粒尺寸的增大,凸模单位压力逐渐减小;晶粒尺寸的变化对于各个阶段成形力变化趋势没有明显的影响。

In order to study the influence of grain dimension on microforming process, at room temperature, micro extrusion forging process with micro copper cylinders which have different grain size were proceeded, and the characteristics of material flow in micro dimension as well as relevant processing parameters were obtained. The result shows that with the increase of grain size, the extruded rod surface is gradually irregular, that is the heterogeneous flow of material is emerged; the unit pressure of upper die is decreased with the increase of grain size; the change of grain dimension has no apparent influence on tendency of form ing load at different forming stage.