Abstract: Circuit breaker ablation process is an important process of self-energizing circuit breaker opening and closing, contact separation, SF₆ gas in the high current and high voltage under the action of the breakdown, resulting in extremely high temperature and pressure of the plasma, the plasma in the gas blowing and the role of the Lorentz force with the separation of the contacts in the nozzle is constantly being stretched out to the outside of the radiant heat, the nozzle absorbs the heat generated by a large number of PTFE steam, steam will increase the pressure of the arc extinguishing chamber The steam will increase the pressure of the arc extinguishing chamber, enhance the level of air blowing in the flow channel, in favor of the medium between the breaks to recover (arc quenching). Existing research on the ablation enhancement effect and pressure enhancement mechanism is not clear. The results of this paper can provide a theoretical basis for optimizing the ablation performance of the nozzle material to avoid excessive ablation, which has an important guiding value for enhancing the circuit breaker opening performance.