夹芯注最小壳层预填充量的预测及其误差分析

Forecasting of Min Prefilled Polymer Volume Fraction in Sandwich Injection Molding and Analysis of Its Errors

顺序共注射模塑中的芯层熔体前沿冲破是造成共注制品报废的重要原因之一,合理控制壳层预填充量可预防此现象发生。从运动学角度探讨芯层熔体冲破的影响因素,建立预测最小壳层预填充量的方程,并在Moldflow平台上进行验证。发现芯壳层熔体黏度比R较小时,该方程的预测值相对数值模拟结果偏大;反之亦然。

The core-melt front breakthrough was one of the most important reasons in scrap products in the sequential co-injection molding, which could be prevented by controlling properly prefilled volume of skin. From the perspective of kinematics, the reasons which affected the core-melt breakthrough were discussed, and a equation which forecasted min prefilled polymer volume fraction was created. Then above conclusions were validated by Moldflow software. It was found when viscosity ratio of core/skin melt（R） was less ,the forecasting values of the equation were greater than that of numerical simulation ,and vice versa.