Abstract: In this work, with the help of magnetron sputtering coating process, the deposition of aluminum on the surface of micron-sized silica powders was carried out by using aluminum target as a sputtering source to achieve a new type polyhedral metallic pigment on a large scale. The differences between the polyhedron metallic pigments and traditional aluminum pigments were analyzed, which were mainly focused on the flow lines and weld lines in plastic parts. The results indicated that the polyhedron metallic pigments presented a better metallic texture in comparison with the traditional aluminum ones. Furthermore, the flow lines in the relevant parts almost disappeared completely, and the weld lines were also reduced significantly. The reasons for the differences between the flow and weld lines were further analyzed and explained theoretically. The effect of polyhedron metallic pigments on the physical properties of plastic parts was investigated, and meanwhile the effect of processing technology on the appearance of polyhedral pigments was also evaluated. The free-spraying parts with no flow lines could be directly injection molded by using a mixture of the polyhedral metallic pigments and thermoplastics. This processing procedure is more cost-effective and more ecologically friendly. The free-spraying parts have been approved by consumers due to a great commercial success.