High-voltage surge impact on thick-film sensors for structural health monitoring: Resistance and noise spectroscopy analysis

Abstract

This study explores the effects of high-voltage electrical surges on the performance and structural integrity of thick-film strain sensors developed for structural health monitoring in steel infrastructure. The sensors were fabricated using screen-printing techniques with a bismuth lead ruthenate-based resistive composition deposited on alumina ceramic substrates. To simulate realistic operational conditions, the sensors were mounted on steel beams and subjected to four-point bending to induce mechanical strain. Following mechanical loading, controlled high-voltage surge pulses were applied to emulate extreme electrical events. Sensor response was characterized before and after surge exposure using both static resistance measurements and current noise spectral analysis. While resistance measurements showed limited change, noise spectroscopy revealed microstructural damage undetectable by conventional means. The findings highlight the degradation mechanisms arising from electromechanical stress and demonstrate the effectiveness of noise spectroscopy as a non-destructive diagnostic tool. These results support the use of thick-film sensors in electrically demanding environments.