Analysis of temperature profiles and protective mechanism against dry-band arcing in silicone rubber nanocomposites

The paper discusses the mechanism by which nanofillers improve the erosion resistance of silicone rubber nanocomposites under simulated conditions of dry band arcing. Various micro-nano composites are studied, including microfiller, nanofiller, combinations of both, and with a commercial surfactant to improve the dispersion of the nanofiller. The thermal conductivity of the composites, measured using a standard method, shows higher thermal conductivity when the nanofiller is well dispersed. A thermal model is developed and solved with finite element method (FEM) to examine the temperature profile in the modelled nanocomposites under laser heating, which simulates the hot spot from dry band arcing. The hot spot is compared to the measured temperature profile by an infrared camera. SEM, EDAX, and XRD techniques are used to analyze the thermally decomposed silicone residue after laser heating to elucidate the protective mechanism in the silicone rubber nanocomposites.