ON THE DYNAMICS OF GAS-ASSISTED INJECTION-MOLDING PROCESS

Gas-assisted injection molding offers a cost effective means of produc tion of hollow plastic parts and a solution to the problems associated with conventional injection molding, such as warpage and sink marks. In this paper, a computer-aided engineering tool is developed and appl ied to the analysis of this process. Dynamic animation of the analysis result is offered in order to mimic the dynamics of polymer melt, gas injection, and penetration behavior during the filling and gas-packin g stages. Also, the influences of processing conditions, mold design a nd material properties on the molding behavior of a commercial product ion mold is investigated in order to establish useful design guideline s.