FIBER MAT DEFORMATION IN LIQUID COMPOSITE MOLDING .1. EXPERIMENTAL-ANALYSIS

When a resin in injected into the mold in liquid composite molding, th e preplaced fiber mat may deform near the inlet gate because of the hi gh momentum carried by the injected fluid. A fiber free region near th e gate followed by the fiber mat deformation may emerge. This phenomen on is most likely to occur when the stacked fiber mats have low permea bility and the resin has high viscosity. A set of mold filling experim ents were carried out using an instrumented metal mold and a small tra nsparent mold to investigate the fiber mat deformation during mold fil ling. Experimental results showed that the fiber mat deformation was l imited to a small region near the gate and that deformation greatly re duced the molding pressure. A forced fiber mat deformation employing a modified gate design was proposed to facilitate mold filling in liqui d composite molding.