The Application of SEM in the Decay-Like Aging of Silicon Rubber Composite Insulator

Scanning electron microscope (SEM) has been widely used in the field of materials science because of its excellent microscopic amplification performance, but it is seldom used in the field of high voltage. SEM can visually reproduce the micro morphology of the mandrel surface and find the defects that are difficult to be observed by the naked eye, which is convenient for the experimenters to summarize the micro morphology characteristics of the aged core rod and determine the equivalence between the accelerated aging test in the laboratory and the actual aged samples in operation. In this paper, SEM was used to observe the surface of the core rod samples after heat aging, acid soaking and electric erosion, and the results were compared with the actual decay-like aged samples in operation. The results show that the serious degradation of epoxy resin, the exposure of glass fiber, the uneven fracture and the failure of interface between fiber and resin can be clearly seen by SEM. At the same time, it can also find the residue on the fiber after the epoxy resin is powdered and the bubbles and cavities formed when the epoxy resin is degraded. Meanwhile, SEM can be used to find the similarity between the laboratory aging sample and the actual sample, and prove the equivalence between them to a certain extent.