射出成形品のリブ配置が初期そり挙動に及ぼす影響

抄録

We reported the displacement (initial warpage) observed just after a molded part with ribs taken out from a mold affects the final warpage in injection molding and has close relationship with the accuracy of numerical analysis. In this paper the main influence of the rib geometry on the initial warpage was investigated using molding parts with different rib layout. As a result, it was confirmed that the stress which is asymmetrical in the wall direction is generated by inhomogeneous restriction from the ribs geometry of the mold cavity when a molten polymer solidifies in the mold, and this stress is the main cause of the initial warpage.