Prediction of mechanical properties of carbon nanotube‒carbon fiber reinforced hybrid composites using multi-scale finite element modelling

Abstract

The mechanical properties of unidirectional carbon nanotube (CNT)‒carbon fiber (CF) reinforced hybrid composites are scrutinized. Due to lack of comprehensive model, a 3D multi-scale model considering debonding damage is developed, covering from nano-to macro-scale. Considering three different configurations of grown CNT's on the fiber surface, the interfacial behavior is investigated. The results reveal that: (Ⅰ) an extraordinary influence of CNT's on the fiber-matrix interfacial properties, particularly in the composites containing axially and randomly oriented CNT's, (Ⅱ) considering two hybrid systems, composites with CNT's‒coated fibers demonstrate outstanding improvements in the interfacial behaviors than those with CNT's in matrix, (Ⅲ) the pronounced effect of non-bonded interphase region on the interfacial properties, while no influence on the Young's moduli is observed, and (Ⅳ) the presence of CNT's augments the transverse Young's modulus, however, it exhibits negligible effect on the longitudinal direction. The outcomes are consistent with experimental data and can be utilized in designing of CNT‒CF multi-scale composites.