The Effect of Thickness on the Tensile and Impact Properties of Reinforced Thermoplastics

The properties of reinforced thermoplastics are affected by the amount of skin and core developed within a part during the injection molding process. Since the thickness of a part greatly influences the amount of skin and core developed within a molded part, thickness also affects the properties of reinforced thermoplastics. This study compares the tensile strength and modulus of several short and long fiber reinforced thermoplastics at 2.0, 3.2, 4.4, and 6.4 mm wall thicknesses. Falling dart impact properties of the short and long fiber reinforced materials are also examined at 3.2 and 6.4 mm wall sections. The results indicate that the tensile properties of the reinforced crystalline resins are more affected by thickness than the reinforced amorphous resins. The study also shows that increasing wall thickness from 3.2 to 6.4 mm will significantly increase the impact energy absorption characteristics of several reinforced thermoplastic materials.