Predicting the kinetics of hysteretic self-heating of GFRPs under high-frequency cyclic loading

摘要

Hysteretic self-heating effect emerges in aerospace, automotive and marine structures subject to vibrations with high amplitudes and frequencies, causing the degradation of mechanical properties and, in some cases, failure of structural materials. In this work, nonlinear deformation of GFRP at single and cyclic tension along with warp yarns at quasi-static conditions was investigated. The self-heating effect at the frequency of 25 Hz using a thermal imaging camera was analyzed. As a result, the analytical model of hysteretic heat generation at cyclic loading was developed. For this, we have approximated single loading stress-strain curves by Ramberg-Osgood functions and calculated the width of hysteresis loop at cyclic loading with the given stress amplitude. It helped to develop the methodology for the prediction of samples self-heating under conditions of natural convective heat transfer and compare the calculated and experimental data of thermal progress. The life of GFRP at cyclic loading is estimated using the criterion of reaching glass-transition temperature obtained from the tests on the dynamic mechanical analyzer (DMA).