Experimental and Numerical Study of Mechanical Behavior of Thermoplastic Composites Considering Residual Stress

In order to predict the mechanical behavior of glass fiber reinforced plastics (GFRP) under the influence of residual stress, a three-dimensional representative volume element (RVE) model with the material microstructure characteristics and physical failure criteria is constructed in the framework of computational micromechanics. The accuracy of RVE model is verified by designing macroscopic transverse tensile experiment. On this basis, the damage failure of GFRP under transverse tensile load is studied in detail, and the influence of residual stress on the transverse tensile and shear mechanical behavior of thermoplastic composites is further analyzed. The results show that the RVE model can accurately characterize the macroscopic properties and mechanical behavior of GFRP. The transverse tensile strength of GFRP is controlled by the properties of the matrix, and the damage evolution is influenced by the matrix plastic damage and the interface debonding. The residual stress results in initial damage to both the matrix and the interface, which reduces the transverse tensile and shear strength of GFRP to varying degrees.