Two methods to calculate the thickness of HTV surface with laser-induced breakdown spectroscopy

Abstract

Silicone rubber composite materials have been widely used in high voltage field, especially high temperature vulcanized silicone rubber (HTV) polymer, used as insulators in transmission lines. During the service time, aging process would happen from surface to bulk with HTV sheds, and measuring the aging layer thickness was a key problem. To evaluate the performance of the insulator in transmission line, in this paper, firstly, we analyzed the spectrum of HTV material with laser pulse number via Laser-induced breakdown spectroscopy (LIBS) technique. It was noted that some spectral lines of the soluble salt elements can characterize the aging change with depth, and the thickness of aging layer was calculated accordingly. Secondly, we studied the plasma temperature property of samples with depth. We found the constraint of limited space in ablation pits can significantly affect the plasma temperature. With the comparison with new samples, we calculated the thickness of the aging layer. Both methods were feasible, and aging layer thickness of HTV polymer surface could be obtained quickly.