Study of silicone rubber used at external insulation of high voltage with laser-induced breakdown spectroscopy (LIBS)

Abstract

RTV coatings and composite insulators have been widely used in electric insulations to prevent pollution flashover. Many materials analysis methods have been applied to get more information about the content, elemental concentration and the structure of silicone rubber, such as IR spectrum, X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD). Laser-induced breakdown spectroscopy (LIBS) is an effective technique, unlike other conventional surface analysis techniques requiring cumbersome sample preparation. LIBS can be performed in situ with no sample preparation. In this paper, we showed that LIBS can be used to acquire the elemental content of silicone rubber composites. Properties of the plasma inspired by pulse laser from silicone rubber were investigated. Several elements of the compositions in silicone rubber was found, such as C, O, Si, Mg, Al. Meanwhile, it was found that the depth of the laser ablation crater was linear relationship with laser pulses.