COMPUTER-AIDED-ENGINEERING (CAE) FOR THE GAS-ASSISTED INJECTION MOLDING PROCESS

GAS-ASSISTED INJECTION MOLDING PROCESS HAS BEEN CLAIMED BY ITS PROPONENTS AS THE MOST IMPORTANT DEVELOPMENT FOR THE INJECTION MOLDING PROCESS SINCE THE INVENTION OF RECIPROCATING-SCREW INJECTION MOLDING MACHINE. THIS PROCESSCONSISTS OF A PARTIAL INJECTION OF POLYMER MELT TO THE MOLD CAVITY FOLLOWED BY AN INJECTION OF COMPRESSED GAS WHICH PENETRATES AND, IN PRINCIPLE, HOLLOWS OUT A NETWORK OF PRE-DESIGNED, THICK-SECTION GAS CHANNELS UNTIL THE CAVITY ISFILLED. IT IS BELIEVED THAT ONCE THE PROCESS IS WELL DEVELOPED AND UNDERSTOOD, IT CAN PRODUCE MANY INJECTION MOLDED PARTS WITH LIGHT WEIGHT AND HIGH RIGIDITY AND WILL PROVIDE TREMENDOUS FLEXIBILITY IN THE DESIGN OF PLASTIC PARTS. THE DEVELOPMENT AND APPLICATION OF THIS PROCESS, HOWEVER, HAVE BEEN VERY SLOW AND IN AN AD-HOC MANNER DUE TO THE LACK OF ENGINEERING KNOW-HOW TO PREDICT THE PROCESS BEHAVIOR. THE ANALYSIS OF THE PROCESS INVOLVES FLOW OF TWO DRASTICALLY DIFFERENT MATERIALS IN A GEOMETRICALLY COMPLICATED MOLD CAVITY. THIS PROPOSED STUDY IS AIMED AT ESTABLISHING THE SCIENTIFIC BASIS AND ATTAINING AN ENGINEERING SOLUTION FOR CHARACTERIZING THIS INNOVATIVE PROCESS. WE WILL MAKE EFFORTS ON BOTH THEORETICAL AND COMPUTATIONAL ASPECTS AND DEVELOP AN EFFICIENT, RELIABLE COMPUTER ANALYSIS TOOL AND DESIGN GUIDELINES. SUCCESSFUL RESULTS OF THIS RESEARCH WOULD NOT ONLY EXPEDITE THE DEVELOPMENT AND ACCEPTANCE OF THIS PROCESS, BUT ALSO MAY ADDA NEW DIMENSION TO THE PLASTIC PART DESIGN.