Deformation-dependent electrical resistivity of fiber-reinforced nanocomposites: A concentric cylindrical model approach

Abstract

Fiber-reinforced composites have seen growing demands and widespread use in a variety of fields, including aviation, civil engineering, and the automobile industry. Fiber-reinforced composites must be monitored by nondestructive methods because of their tendency to have complicated and often visually undetectable failure mechanisms. Incorporating self-sensing capabilities into composites through nanofiller modification to leverage the piezoresistive effect is one approach for monitoring these materials. In this method, electrical resistivity is a function of mechanical strains, allowing for intrinsic self-sensing. To date, predictive modeling efforts in this field have mostly concentrated on microscale piezoresistivity. Research on modeling resistivity changes in macroscale fiber–matrix material systems has been limited, and even less research has been conducted to evaluate the impact of continuous fiber reinforcement. To bridge this gap, an analytical model that predicts changes in the resistivity of a material system with nanofiller-modified polymer and continuous fiber reinforcement is proposed. The cornerstone of this strategy is the establishment of an electrical concentric cylindrical model. We begin by defining our domain, which consists of concentric cylinders representing a continuous reinforcing fiber surrounded by a nanofiller-modified matrix. Next, the system is homogenized such that we can predict the change in the axial and transverse resistivity of the concentric cylinders. It is envisaged that the results herein presented will serve as a stepping stone towards the creation of a laminate theory of piezoresistivity.