Micro-Mechanics Modeling of Compressive Strength and Elastic Modulus Enhancements in Unidirectional CFRP with Aramid Pulp micro/nano-fiber Interlays

Abstract Compressive strength and elastic modulus of unidirectional carbon fiber reinforced polymer (UD-CFRP) have been enhanced experimentally by using soft micro-length Aramid pulp (AP) micro/nano-fiber interlays. This study presents a micro-mechanics model to prove theoretically such enhancements in the compressive strength and elastic modulus of UD-CFRP are possible. The micro-mechanics model recognizes the importance of in-situ formed graded interfacial region between carbon fiber plies generated from the random distribution and out-of-plane movements of micro-length AP micro/nano-fibers. The micro-mechanics model shows that even an areal density of only ~4 g/m2 of AP micro/nano-fibers (with the interlay thickness