Surface quality: improving the quality perception of molded parts

A novel assessment method based on three-dimensions technology has been proposed for analysing the surface quality of injection-molded parts. Starting from a mold having a leather texture engraved on it, the quality of replication on the surface of a polypropylene molded part has been studied as a function of the injection parameters. In order to establish a relationship between quality appearance and surface topography, amplitude parameters and functional parameters have been compared. A white light interferometer (WLI) was used to assess the surface and a scanning electron microscope (SEM) was employed to detect small features on the surface. The results indicated that, in terms of quality perception, functional parameters are more accurate than amplitude parameters for quantifying the mold replication on the polypropylene surface