Properties of Temperature-Dependent Nonlinear Conductivity of SiR/SiC Composites

This paper focuses on the temperature-dependent nonlinear conductivity of the field grading material (FGM) based on high temperature vulcanized (HTV) silicone rubber (SiR). The nonlinearity was achieved by mixing silicon carbide (SiC) particles with the SiR matrix. The conductivities of the samples were measured at temperatures of 30–90 °C. The experiment results showed that the SiR/SiC composites had nonlinear conductivity when the SiC content exceeded 30 phr in the entire temperature interval. The conductivity increased, and the threshold field of conductivity decreased at high temperature. In the SiC mixed samples, a convergence trend appeared at high field at temperatures below 70 °C textbf. The mobility increased with the increase in temperature. This trend became more obvious at high temperature. In addition, compared with voltage, the temperature had a more remarkable effect on the carrier mobility.