Numerical and experimental evaluation of surface properties of embossed decorative injection-molded parts

In this study, short-glass-fiber-reinforced poly(butylene terephtalate) with embossed decorative patterns was produced by an injection molding using a plated-shape cavity with embossed fine convexo-concave patterns on a fixed one-sided surface. The influence of the molding conditions, the fiber contents, and the fiber orientation distributions on the embossed-surface quality of the injection-molded parts was investigated by experiment methods. A method for evaluating the quality of the embossed surface using a spectrum analysis computes Fourier transform from surface roughness data was presented. Further, the software CIMP-PACK3DM was employed to analyze the resin flow in the specimens using the finite element method. The numerical results were in good quantitative agreement with the experimental methods. Consequently, the study aimed to find out an approach for produce a favorable surface quality from considering the resin surface temperature and resin pressure in the filling process, or the fiber orientation prediction of final part.