Fracture toughness and fatigue behavior of spider silk and S-glass epoxy composites: An FEM approach

In this paper, a detailed study of fracture toughness and fatigue behaviour analysis of Spider silk and S-glass epoxy is presented. The usage of synthetic composite fibers is being increased rapidly. However it is expected that, the continuous applications of these fibers in the aerospace sector may tend to decline in the near future in the light of availability of natural fibers. The semi-natural composite proposed in the present work consists of dragline Spider silk as natural fiber and epoxy as matrix. In the world of natural fibers, Spider silk is recognized as the wonder fiber for its unique combination of high strength and rupture elongation. The orientation of the fiber in the matrix is made with reference to the failure resistance of each orientation. The fracture toughness and fatigue life of Spider silk and S-glass epoxy is analyzed using data from literature and verified by FEM (finite element method) simulations. The fracture toughness, stress-strain behaviour and failure of the Spider silk epoxy composite are compared with that of S-glass epoxy composite. The results show that the Spider silk epoxy composite exhibits higher toughness and lesser failure at high stress levels. Therefore it is concluded that Spider silk epoxy composite could be a better replacement for S-glass epoxy composite for the prospect of potential green composite technology in aerospace industries.