Effect of Layer Structure on Dynamic Response and Failure Characteristics of Carbon Fiber Reinforced Aluminum Laminates (CARALL)

Abstract

The effect of placing carbon fiber reinforced composite layers exterior or interior to the aluminum layers on the low-velocity impact performance of CARALL FMLs was investigated in this research study. In this study, CARALL laminates having 3/2 configuration, with aluminum in the outer layer for the first case (CARALL A) and one with carbon fiber composite (CFC) layer in the outer layer (CARALL B) were prepared using a vacuum press without using any adhesive film. In addition, CARALL-A FML was modified with a thin veil cloth layer between CFC and aluminum layers (CARALL-C). Force–displacement histories, damage morphologies and energy absorption capabilities of these laminates in relation to different energy levels are presented and discussed. The influence of resin rich layers (veil cloth) at the interfaces of aluminum and carbon fiber/epoxy layers on the impact behavior and damage size is also investigated. CARALL-A FMLs absorb the energy mainly through plastic deformation and delamination initiation and propagation whereas CARALL-B absorbs the impact energy through penetration and perforation of the laminate. The introduction of resin rich layers (veil cloth) affects the overall dynamic response with higher contact forces, smaller ultimate central deflections, reduced delamination damage area, and provides hindrance to the growth of cracks in the non-impacted aluminum layer and thereby increasing the impact resistance of CARALL-C FMLs.