Drop Weight Impact Properties of (CO) Injection Molded Short Glass Fiber/Short Carbon Fiber/Polyamide 6 Hybrid Composites

Abstract

Polyamide 6 (PA 6) composites with short glass fiber (GF)/short carbon fiber (CF) hybrid fiber reinforcement were produced using two types of injection molding techniques, i.e., the conventional and co-injection molding machines. In the latter, sandwich skin-core hybrid composites were produced. The fiber volume fraction for all formulations was fixed at 0.07. The composites were subjected to drop weight impact tests, to determine their impact strength, impact energy, ductility index (DI) and ductility ratio (DR). It was observed that the PA 6 formulation exhibited the highest impact strength and impact energy values whereas carbon fiber/PA 6 (CF/PA 6) exhibited the highest DI and DR values. The carbon fiber skin/glass fiber core/PA 6 (CF_S/GF_C/PA 6) sandwich skin-core hybrid composites showed the highest impact energy and impact strength values among hybrids. The glass fiber skin/carbon fiber core/PA 6 (GF_S/CF_C/PA 6) hybrids on the other hand showed the highest DI and DR values among hybrids. Failure mechanisms in the matrix and composites, assessed by scanning electron microscope (SEM), were discussed in relation to the effects of fiber incorporation and its effects on the ductility of the composites, with particular emphasis on the hybrid composites.

Keywords

(co)injection molding hybrid composites drop weight impact polyamide 6

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