Evaluation of adhesion of continuous fiber–epoxy composite/aluminum laminates

Abstract

Continuous fiber composite/metal laminates (FMLs) offer significant improvements over currently available composite materials for aircraft structures due to their excellent fatigue endurance and low density. Glass fiber–epoxy composite laminae and aluminum foil (GLARE) are commonly used to obtain these hybrid laminates. In this work, FMLs were produced by treating the aluminum foil to promote adhesion bonding by two methods: sulphuric chromic acid etching (SCAE) and chromic acid anodization (CAA). The surface treatments were evaluated by contact angle, roughness and scanning electron microscopy techniques. In order to compare different families of fiber composite/metal laminates, carbon fiber and glass fiber fabrics were used as reinforcements for the hybrid laminates. The adhesion of the hybrid laminates was evaluated by scanning electron microscopy (SEM) and three-point bending test. CAA resulted in better wetting properties. The interlaminar shear strength results for both carbon fiber-epoxy/metal and glass fiber-epoxy metal, were close to the interlaminar shear strength results found in the literature (approx. 40.0 MPa).

Keywords:

• HYBRID LAMINATES
• FIBER/METAL LAMINATES
• COMPOSITES
• CARBON FIBER
• GLASS FIBER
• GLARE