A new method to measure RTV coatings thickness with laser-induced breakdown spectroscopy (LIBS) technique

Abstract

Room temperature vulcanized silicone rubber (RTV) coatings have been widely used in the world to prevent the pollution flashover in transmission lines. Thickness of the RTV coatings which was hard to measure with regular methods, was one of the most important properties and required by State Grid Company. As a fast and online analysis method, laser-induced breakdown spectroscopy (LIBS) has been applied in different fields. With LIBS, this paper studied the depth of the laser-ablated craters and the emission spectra of RTV coatings. Using a laser, focusing on the coating surface, together with a spectrometer and the scanning electron microscope (SEM) for observation, the linear relationship between the crater depth and the number of laser pulses was observed and the emission spectra were observed. The result showed that the depth of laser-ablated craters on RTV had a linear relationship with the number of laser pulses, which could be further applied to the measurement of the RTV thickness of coatings.