Abstract: Abstract: With the acceleration of ultra-high voltage construction in China, issues such as excessive short-circuit current and the risk of large-scale power outages pose a serious threat to the safe and stable operation of the system; To ensure the safe and reliable operation of the power system, it is necessary to continuously increase the breaking capacity of circuit breakers and have higher reliability and longer lifespan. The erosion resistance of the nozzle seriously affects the safe operation of circuit breakers. Therefore, researching high-performance nozzle materials is of great significance for improving the overall performance of circuit breakers. This paper uses polytetrafluoroethylene as the substrate and prepares two types of nozzles with fillers of 0.3% molybdenum disulfide+9 boron nitride and 0.3% molybdenum disulfide. The L90 experiment of the high-voltage switch with a rated short-circuit current of 80kA was conducted at Xi''an High Voltage Electrical Equipment Research Institute, and the results showed that the nozzle with 0.3% molybdenum disulfide+9 boron nitride filler had better erosion resistance. At the same time, it was proved that both types of nozzles can be opened normally. The nozzle with the combination of the two fillers has significantly higher erosion resistance than the nozzle with 0.3% molybdenum disulfide filler.