Experimental investigation of the dynamic properties of fiber-reinforced composites

Abstract

Carbon fibers are increasingly used in thermoplastic composites by virtue of their favorable mechanical, thermal, and electrical properties. However, their relative high price compared to other reinforcements, such as glass fibers, is keeping carbon fibers from being widely utilized. Short fiber-reinforced composites are very attractive because of the ease in their fabrication, low cost, and mechanical properties which are superior to those of continuous fiber-reinforced composites. Recently, a new type of carbon fiber, vapor grown carbon fibers (VGCFs), has gained interest. As a result of their production method, VGCFs combine potentially low production costs with encouraging mechanical, thermal, and electrical properties compared to conventional ex-pitch or ex-PAN carbon fibers. This makes them of specific interest for applications where currently the conventional fibers are too expensive and glass fibers cannot provide the required thermal and electrical properties. In this paper, experimental investigation of longitudinal storage modulus and loss factor of unidirectionally aligned VGCF/pp nanocomposites has been made using DMA (dynamic mechanical analyzer). Further, the results obtained from DMA have been compared with FEM results and also with the Mori-Tanaka model. It has been found that experimentally measured longitudinal modulus shows good agreement with both FEM and Mori-Tanaka results.