Prediction of the inter-fiber mechanical properties of composites: Part II Failure criterion based on micromechanics and cross-scale stress calculation

A novel inter-fiber failure criterion of composites based on micro-scale failure mechanism is proposed in this paper. The composites failure is determined by the failure of constituents near interface, where the micro-scale stress is “risk”. A cross-scale stress calculation formula is derived according to inclusion theory, and proved precise by comparing with the micro-scale simulation results. The accuracy of the failure criterion is verified through the experimental results and simulation results of micro-scale model under biaxial stress. The failure criterion considers the micro-scale stress distribution, fiber volume fraction and elastic properties of constituents, and can give precise predictions on the strength and failure angle of fiber reinforced polymer composite.