MODELING OF FRACTURE IN HETEROGENEOUS MATERIALS

Abstract

Biological composites like nacre, teeth and bone achieve superior mechanical properties through the staggered structure, which consists to hard phase in form of platelets embedded in soft matrix. Although various studies have been conducted to understand the structure-mechanical properties correlation, but they are based on the assumption of perfectly bonded interface between the platelets and matrix. In this study, we present a mathematical framework combining the phase eld method and cohesive zone model to investigate the role of interface properties on the emergent behaviour of staggered structures. An analytical shearlag model incorporating the e ect of imperfect interfaces is also presented and results are compared against the numerical model. A staggered structure consisting of multiple platelets is analysed and parametric studies are conducted to study the role of interface properties on activating di erent fracture mechanisms. Further the e ect of platelet aspect ratio is presented. The results shows that the interface properties strongly in uence the nal fracture patterns and overall toughness and sti ness of the structure. A speci c combination of interface strength and interfacial energy needs to be selected in order to highest combination of overall mechanical properties.