Nondestructive Testing Technique for Silicon Rubber Aging Based on Terahertz Spectroscopy

The aging and degradation of composite insulating materials can significantly compromise the safety and stability of power systems. Developing reliable techniques to assess the extent of aging is therefore essential for reducing the incidence of insulation failures. To address the accelerated aging of high-temperature vulcanized (HTV) silicone rubber in high-altitude environments with intense ultraviolet radiation—where existing detection methods exhibit limitations—this study proposes a nondestructive testing approach utilizing terahertz reflection spectroscopy. By employing least squares support vector machine (LSSVM) regression, this research establishes a relationship between the terahertz absorption spectra of HTV silicone rubber and the content of its key chemical constituents. Monitoring changes in these components through terahertz spectroscopy offers an effective means of evaluating the performance degradation of HTV silicone rubber.