Thermal aging effects on the surface potential under electron beam irradiation (SEM) of XLPE insulation cables

A scanning electron microscope (SEM) is employed to investigate the Thermal aging effect on the surface potential decay of cross-linked polyethylene (XLPE) under electron beam irradiation. We have subjected the material to the X-ray spectra monitored with X-ray spectrometer attached to the special adapted arrangement of SEM. The variation of charging process of XLPE is monitored with measuring the surface potential in response. The effect of thermal aging on the dynamic trapping of XLPE charge processes was evaluated. The most suggestion of the observed behavior is the diffusion of cross-linking by-products to the surface of sample that acts as traps for injected electrons. The oxidation which is a very important form of XLPE degradation has an effect at the advanced stage of the aging process.