Terahertz detection of fillers in solid insulating materials

Solid insulation materials undertake important insulation tasks in power insulation. For the analysis of fillers in solid insulation, there are few non-destructive testing methods currently used, and the accuracy is not high. The destructive testing accuracy of samples is high, such as thermogravimetric analysis, but the operation is complicated and the testing requirements are high, which cannot meet the rapid and non-destructive testing of silicone rubber. In this paper, silicone rubber commonly used in solid insulating materials is taken as the research object, and different samples are made by changing the filler content in rubber, and a terahertz transmission detection platform is built in the laboratory to detect the samples, and the terahertz time domain signal, refractive index and terahertz absorption rate of the samples are obtained. Finally, by analysing the terahertz absorption rate of the sample, the relationship between aluminum hydroxide content and terahertz absorption rate is obtained at the characteristic frequencies of 1.21thz and 1.33thz of silicone rubber. This method can detect the content of aluminum hydroxide filler in silicone rubber in a non-contact and non-destructive way.