Diffusion, erosion and thermal distribution in Gamma-ray irradiated ATH and SiO<inf>2</inf>doped SiR nano-micro composite

Gamma-ray irradiation severely degrades the diffusion, erosion and thermal properties of silicone rubber (SiR) used in the high voltage insulation cables. Therefore to improve the properties of SiR, blending of alumina tri-hydrate (ATH) and silica (SiO2) micro and nanoparticles in the base SiR matrix is a subject of great interest for high voltage utilities. In this context, the current study involves the synthesis and performance evaluation of 1000 kGy gamma-ray irradiated undoped SiR, SiR+40% micro ATH, SiR +4% nano SiO2 and SiR filled with 37% micro ATH+3% nano SiO2. To assess the diffusion properties, all the samples were immersed in the strong electrolytic NaCl solution and the degradation of samples were analyzed through weight gain measurements. Further, to evaluate the erosion resistance, the samples were subjected to water droplet initiated corona discharges using IEC 60112 experimental set up. Thermal distribution analysis post corona discharge was performed for all composites using an infrared camera.