Using 3D injection molding simulation to explain emerging two- and three-dimensional surface structures of ABS and PC/ABS parts within the process of electroplating on plastics

Injection molding simulation (Sigmasoft) is applied to increase the understanding of the emerging surface properties of ABS and PC/ABS parts after etching within the process of electroplating on plastics. The investigation is based on surface information gained by already published analyses with two-dimensional data (Scanning-Electron-Microscope combined with image analysis) and three-dimensional information stemming from confocal microscopy. With the aim of detecting correlations, this data is compared to local simulation results (e.g. shear rate, temperature, viscosity). The consequent pattern of results indicates a substantial correlation between the deformation tendencies of the butadiene particles and the simulated shear rates. Furthermore, the effect of local temperatures on the relaxation of the butadiene can be detected. The investigation is performed at four different positions on the part and the simulation results show differences caused by geometry. In addition, the simulated shrinkage potential is identified as important indicator of residual stresses within the part. The results show that higher simulated shrinkage potential affects the etching process and the resulting cavern structures, which are quality defining for the layer system. This paper focuses on a selection of results for ABS out of a huge amount of results generated for ABS as well as for PC/ABS.