A micromechanical model for the temperature dependent tensile strength of cross-ply fiber reinforced polymer composites

The tensile properties of cross-ply fiber reinforced polymer (FRP) composites at different temperatures have been an essential issue of concern. This work established a temperature dependent tensile strength (TDTS) micromechanical model for cross-ply FRP composites according to the Force-Heat Equivalence Energy Density (FHEED) principle and failure analysis. The combined effects of temperature, fiber strength and its scatter, especially the evolution of constituent' properties and residual thermal stress with temperature on the tensile strength are considered in the model. The predicted results of TDTS by the model realize a reasonable agreement with the available experimental results. Moreover, the influencing factors analysis regarding the evolution of tensile strength with temperature were performed. This study contributes a reliable theoretical model for predicting the TDTS of cross-ply FRP composites, and provides useful insights for strength evolution with temperature and composite strengthening.