微结构塑件的注塑充填尺度效应  

Scale Effect of Injection Filling for Microstructure Plastic Parts

作　　者：邓爱林 薛松 徐斌 Ailin Deng;Song Xue;Bin Xu(School of Manufacturing Science and Engineering,Key Laboratory of Testing Technology for Manufacturing Process,Ministry of Education,Southwest University of Science and Technology,Mianyang 621010,China)

机构地区：[1]西南科技大学制造科学与工程学院制造过程测试技术教育部重点实验室,四川绵阳621010

出　　处：《高分子材料科学与工程》2020年第3期85-95,共11页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(51475395);西南科技大学博士基金(13zx7153)。

摘　　要：微尺度聚合物熔体流动具有明显的尺度效应,模具温度和注射速率是微注塑充填流动的关键影响因素。文中采用微细电火花铣削技术设计分别制造了一模八腔的带有200μm和300μm微孔的注塑模具。以聚丙烯(PP)进行单因素充模流动工艺实验,研究了模具温度和注射速率对直径为200μm和300μm微圆柱充填高度影响规律。结果表明,当模具温度为30℃和注射速率为60%时,直径200μm微圆柱孔的充填高度小于直径300μm微圆柱孔的充填高度,且Ⅰ型腔的微圆柱充填高度大于Ⅱ的充填高度。随着模具温度升高和注射速率增加,2种微孔充填高度差在减小,Ⅰ型腔和Ⅱ型腔之间的充填高度差值也在减小。可见,升高模具温度和增加注射速率可以减少微尺度效应对微圆柱孔充填高度的影响,同时,还可以减小流动不平衡程度。Micro-scale polymer melt flow has obvious scale effect.Mold temperature and injection rate are the key factors affecting micro-injection filling flow.The micro electrical discharge machining(EDM)milling technology was used to design the injection molds with a eight-cavity mold with various diameter holes ranging from 200μm to 300μm.Polypropylene(PP)was used to carry out single factor filling flow experiments.The effects of mold temperature and injection rate on filling height of micro-cylinders with diameters of 200μm and 300μm were studied.The results show that the filling height of micro-cylindrical holes with the diameter of 200μm is less than that of micro-cylindrical holes with the diameter of 300μm,and the filling height of micro-cylindrical holes with cavity I is higher than that of cavity II when the mold temperature is 30℃ and injection rate is 60%.With the increase of mould temperature and injection rate,the difference of filling height between the two kinds of micro-holes decreases,and the difference of filling height between the cavity I and the cavity II decreases.It can be seen that increasing mold temperature and injection rate can reduce the influence of micro-scale effect on filling height of micro-cylindrical holes,and at the same time,it can also reduce the degree of flow imbalance.

关 键 词：微注塑成型 微圆柱 模具温度 注射速率 流动不平衡 

分 类 号：TQ320.662[化学工程—合成树脂塑料工业]