Prediction of the Residual Tensile Strength after Solid Particle Erosion of UD-GF/PP Composites

Abstract

In the present work the residual tensile strength of unidirectional (UD) glass fibre (GF) reinforced thermoplastic polypropylene (PP) composites after oblique (30) solid particle erosion was investigated as a function of the impact time and relative fibre orientation (parallel, Pa and perpendicular, Pe). A semi-empirical approach initially developed to predict the residual tensile strength after single normal impact [1] and latest successfully adopted for thermo-setting carbon fibre/epoxy (CF/EP) composites [2] worked well for the thermoplastic UD-GF/PP composites studied. A very good agreement was found between the experimental results at 30 erosion angle and the theoretical prediction in both Pa and Pe erosion directions. A comparison of the strength degradation behaviour of UD-GF/PP and CF/EP composites showed that UD-GF/PP presented the onset of its strength degradation considerably earlier but it preserved a higher relative residual tensile strength than CF/EP. The erosion direction in UD-GF/PP had marginal effect on the energy threshold resulting in severe strength degradation, whereas it showed a pronounced effect on the residual tensile strength.