Effect of the Fiber Content on the Quality of the Plastic Injection Molding Product

Abstract

Fiber-Reinforced Thermoplastic (FRT) is widely used in plastic injection molding products. In this paper, the effect of fiber concentration on the quality of the plastic injection molding product is considered numerically. PA6 plastic materials, Schulamid 6, with different Glass Fiber (GF) contents, i.e., 15wt%, 30wt%, and 50wt% are selected for the same part and mold designs and process conditions. The warpage of the plastic product, the pressure loss inside the cavity, the plastic density, the packing pressure, and the volumetric shrinkage were investigated. The governing equations and the boundary conditions are numerically solved by the CAE software for injection molding products with the control volume method in a 3D transient system. The results indicate that the higher the content of glass fiber in Schulamid 6, the lower the fluidity of the melted plastic in the Schulamid 6 between different glass fiber contents of 15wt%, 30wt%, and 50wt%. Consequently, the pressure loss in the cavity is highest for Schulamid 6 GF50. Moreover, high GF concentration enhances the plastic density and leads to low volumetric shrinkage and also small warpage inside the product. Therefore, the quality of the part could be improved with the high GF concentration in plastic, i.e., Schulamid 6 GF 50.