分层厚度对微细电火花铣削加工模具及热压制品表面粗糙度的影响

分层厚度直接影响微细电火花铣削加工的加工效率及表面粗糙度。为了合理规划微细电火花铣削加工的分层厚度,提高加工效率,研究了分层厚度对微细电火花加工的模具型腔及相应热压成形制品表面粗糙度的影响,同时分析了热压成形制品表面与微模具型腔表面之间的关系,以及热压前、后微模具型腔表面轮廓的变化。结果表明:当电极轨迹重叠率一定时,模具型腔底面的表面粗糙度值随着分层厚度的增加而增大;分层厚度对型腔侧壁表面粗糙度无明显影响;热压制品表面轮廓算术平均偏差小于模具型腔表面轮廓算术平均偏差;热压后的模具表面轮廓发生了变化,表面粗糙度值Ra和峰高Rpk减小,峰谷Rvk增大。

Influence of Layer Thickness on the Surface Roughness of Micro Molds Machined by Micro EDM and Hot Embossed Products

The surface quality and machining efficiency of 3D micro cavities machined by micro electro-discharge milling is related to layer thickness in milling. In order to improve machining efficiency of 3D micro-EDM,layer thickness should be determined reasonably. The influence of layer thickness on the surface quality of micro molds prepared by micro EDM and hot embossed products is studied. Furthermore,the surface relationship of micro hot embossed plastic parts and micro-molds,and the variation of surface profile of molds after hot embossed are analyzed. Experimental results show that the bottom surface roughness of mold cavity enlarge along with the increase of layer thickness ,the surface roughness of sidewall of molds is irrelevant to layer thickness ,the variation of micro plastic part surface roughness,Ra,Rvk and Rpk follows those of corresponding micro mold surface roughness. The surface profile of mold cavity has been changed after hot embossed.