Temperature-dependent longitudinal tensile strength model for short-fiber-reinforced polymer composites considering fiber orientation and fiber length distribution

In this study, a temperature-dependent longitudinal tensile strength model for short-fiber-reinforced polymer composites (SFRPCs) is established based on the sensitivities of thermal-physical properties of polymer materials to temperature and our previous work. The effects of temperature, fiber orientation distribution, fiber length distribution and residual thermal stress are considered in this model. The theoretical model is verified by comparison with tensile strength of glass SFRPCs at different temperatures. Good agreement between the model predictions and experimental results is obtained, which indicates the reasonability of the proposed models. Furthermore, the comparisons between the present models and the classical models are discussed, and the influencing factors analysis for SFRPCs is also conducted in detail. This study can not only provide a potential convenient means for predicting the temperature-dependent tensile strength of SFRPCs, but also offer useful suggestions for the material evaluation, strengthening and design.