变曲率ICM聚碳酸酯制品残余应力分布

Distribution of residual stress in ICM polycarbonate parts with variable curvature

结合注射压缩成型(injection compression molding,ICM)工艺特点,运用平面偏振和数值仿真方法,对变曲率聚碳酸酯ICM制品残余应力的分布进行分析,研究不同压缩工艺下残余应力分布特点以及随曲率变化的规律。结果发现:除了浇口和末端小部分区域外,光弹应力条纹环绕制品形状分布;顺序式ICM残余应力条纹有较规整的对称分布结构,同步式ICM充填末端区域残余应力在厚度方向与传统注塑成型区别较为明显,呈现"压-拉"两层应力分布状态;同一平面内,变曲率ICM制品厚度方向残余应力随曲率的减小而递减。除平板制品外,其余四类不同曲率制品的平均残余应力与对应曲率均呈反比例变化关系。研究对优化变曲率透明聚合物制品的设计有一定指导意义。

Based on generating mechanism and mathematical model of residual stress in traditional injection process,plane polarization and numerical simulation method were used to research residual stress distribution of ICM（injection compression molding）products with variety curvature qualitatively and quantificationally.The investigation has shown that residual stress distributions followed the shape of part except gate and end of part region.Well geometric asymmetry of stress fringe were detected in ICM-seq molding,while two layers of stress distribution states at end of part were found in ICM-sim molding.The phenomenon was different from tradition injection molding.Within the same plane,maximum residual stress values were reduced as the decrease of curvature.Meanwhile,inversely proportional relationships between average residual stress and part curvature were obtained for all different type of part（except for plate shape）.It makes sense for optimizing design of optical products with variable curvature.