MULTISCALE TRACTION SEPARATION LAW FOR HYBRID METAL FRP COMPOSITE WITH PATTERNED INTERFACE

Abstract

Hybrid metal composite joint achieve superior mechanical properties through the structured interface which consist of fibre embedded in matrix and also fibre interacting with main interface (epoxy-metal).Although various studies have been conducted to understand the effect of changing the interface in terms of roughness for different heterogenous materials,but in many to reduce complexity they have considered homogenised matrix with structured pattern or roughness in combination of different materials such as metal and composites,but in this work we have considered non-homogenised matrix with fibre and how the fibre are interacting with metal-epoxy interface .In this study we present a mathematical framework combining the phase field method and cohesive zone model to investigate the role of interface properties on the emergent behaviour of structured interface joint..A squared patterned periodic main interface between matal and epoxy with fiber volume fraction of 60 % is analysed and parametric studies are conducted to study the role interface properties on activating different fracture mechanism.Further the role of interface aspect ratio and anisotropy ratio is presented.The results shows that the interface properties strongly influence the final fracture patterns and overall toughness and stiffness of the structure.A particular combination of interface strength and interfacial energy needs to be selected in order to highest combination of overall mechanical properties .