Effects of processing parameters on fiber length distribution and tensile strength of long glass fiber reinforced Nylon66 composites molded parts

This study investigates the effects of processing parameters on the tensile strength and fiber length distribution of long glass fiber reinforced nylon66 composites. This study carried out the injection experiment at different screw speeds in order to take the fiber breakage and length distribution as the basis for the setting of processing parameters. The effects of processing parameters on tensile strength of long glass fiber reinforced nylon66 composites (LGF-Nylon66) were then studied using a tensile test specimen mold with single /double gate design (part thickness of 1.8 mm and 3.6 mm). The experimental results show that increasing the screw speed leads to fiber breakage, shortens the fiber length, and thus affects the tensile strength of long glass fiber reinforced nylon66 composites molded parts. On the other hand, as the melt temperature and the mold temperature increase, the tensile strength also increases. In addition, SEM observation presents that the effect of fiber length and orientation distributions on the weldline tensile strength of the molded specimen is very obvious. These results also show that the interfacial adhesion is required to achieve a desired composite strength.