Mode II fracture toughness of CFRP as a function of temperature and strain rate

Knowledge of the fracture properties of composite materials is fundamental to predict the impact behaviour of the lightweight structures currently used in the automotive industry. Although there is substantial research on mode I fracture behaviour of composites, limited information exists on mode II behaviour. This work aims to fulfil this gap, presenting experimental data regarding the influence of temperature and strain rate on the fracture energy in mode II, GIIC, of composite plates. Significant influence of the strain rate and temperature on GIIC of the composite materials was found. Higher strain rates led to a decrease of GIIC up to 17%. An increase of temperature corresponded to an increase of GIIC up to 15% and a decrease of temperature originated a decrease of GIIC up to 7%.