Finite element simulation of SMC compression molding based onthermo-viscoplastic approach with fiber volume fraction prediction

摘要

SMC (Sheet Molding Compounds) is a thermosetting material whichconsists of unsaturated polyester resin and other additives reinforcedwith randomly distributed chopped fiberglass strands. During thecompression molding cycle, it is very difficult to understand theoverall effects of SMC resin components on flow characteristics andmechanical performance of the molded parts, since mold geometries andprocessing variables are complex. Thus, a three dimensional rigid thermoviscoplastic finite element program including chemical reaction andfiber volume fraction prediction was developed in the present study andapplied to the analysis of compression molding of a SMC charge. Toverify the validity of this approach, numerical fiber volume fractionpredictions were compared to fiber volume fraction data measured byimage processing. Three dimensional simulations under various moldingconditions were carried out to obtain more thorough knowledge of the SMCcompression molding process. Based on this study, it was found that thecurrently developed three dimensional finite element program coupledwith heat transfer and chemical reaction can provide valuableinformation in understanding flow characteristics, fiber volume fractiondistribution, and the curing behavior of SMC compression molding indetail