Simplified Finite Element Method for Resistance Response of Graphene Composites Considering Size Distribution and Agglomeration

The resistance response behavior of graphene composites is vital for the application of flexible sensing materials. In this study, a new simplified finite element analysis (SFEA) method is proposed to predict the electricity and the strain response probability of graphene composites with local agglomerates and normal distribution of filler size. In the SFEA, the conducting channels in the classical tunneling effect are searched algorithmically in fillers rather than in the composite and converted into equivalent circuits to calculate approximately the electrical properties of the composites, which saves computing resources distinctively. The resistance response model was established with a translation algorithm, which is applicable to evaluate the resistance response to large strain load. The effects of the filler length, agglomeration and different size distribution of filler on the electrical properties of the composites are studied as well. The results revealed that the dispersion of agglomerates contributes to the enhancement of the electrical properties of composite materials. However, this enhancement may be weakened with the large size distribution of fillers. Furthermore, the size distribution of fillers exhibits a negative impact on the electrical properties of composite materials. The predicted electrical properties of the static model agree with the experimental data basically. These results are important for the evaluation and design of graphene composites as sensing materials in flexible sensors.