Damage Behavior of CFRP/Titanium Mesh Laminates Under Three-point Bending Loading

Abstract

Fiber Metal Laminates (FML), which is molded by alternately laminating FRP and metal layers, attract attention as hybrid composites material that show excellent fatigue resistance and damage tolerance. However, there is a problem that interfacial debonding between FRP and metal layers tend to occur due to such as an out-of-plane loading. In this research, we introduce mesh-shaped metal layers in FML in order to suppress the interfacial debonding because adjacent FRP layer can stick together through the meshes. The damage behavior such as FRP/metal interfacial debonding is evaluated by observing the cross section during three-point bending tests. CFRP / titanium mesh laminates are molded as a flat plate or a curved plate with a radius of curvature of 50mm by using an autoclave or a hot press. The impregnation of resin depends on the thickness of titanium mesh used, and some voids are found inside. By three point bending tests and cross-sectional observations, it is indicated that the maximum load and absorbed energy are improved and the interfacial debonding was suppressed in the flat specimen. These can be assumed as an effect of adopting the mesh structure for metal layers. Improvement of absorbed energy and suppression of interfacial debonding are also observed in the curved plates.