微结构塑件注射成型特性实验研究

设计制造了一可成型具有微结构的塑件(微流控芯片)注塑模具,利用单因素实验方法研究了各种工艺参数(注射速度、模具温度、注射压力、保压压力和保压时间)对微结构复制不完全和表面缩痕这两种主要缺陷的影响.实验结果表明注射速度和模具温度是影响微结构复制不完全的主要因素;注射压力相对于注射速度和模具温度仅起次要作用;保压压力对其影响较为复杂,复制度随着保压压力的增加先提高后降低.影响芯片表面缩痕的主要因素是模具温度和保压压力.保压时间对微结构复制度的影响很小,但却是塑件整体翘曲变形的主要原因.

Experimental research on injection molding characteristics for micro-structure plastic parts

An injection mold in which microfluidic chip (a kind of micro-structure plastic part) can be molded is designed and manufactured. Using the single-factor experimental method, the influence of different process parameters (injection rate, mold temperature, injection pressure, holding pressure and time) on the incomplete duplication and sink mark of micro-structure plastic parts is discussed. The results show that injection rate and mold temperature are the principal factors in the incomplete duplication, and injection pressure is the secondary factor. The influence of holding pressure on the incomplete duplication is complicated, that is with the increasing of holding pressure, the degree of duplication reduces after the first increase. Mold temperature and holding pressure are two main influence factors on sink mark. Holding time has a negligible effect on the incomplete duplication, but it is the main reason for the warpage deformation.