A new model for the growth stage of surface flashover has been developed according to the experimental results , which is based on the solid band theory . it is suggested that the electron multiplication could be attributed to two processes : one is the secondary electron emission avalanche caused by collisional ionization , the other is the micro - discharge caused by the trap centers of insulator . the trap cente 電子倍增的過程與材料的表面態(tài)直接相關(guān),材料微觀結(jié)構(gòu)的變化和材料的表面處理都能夠?qū)е虏牧媳砻鎽B(tài)的變化,引起材料的表面二次電子發(fā)射系數(shù)以及材料中陷階密度和分布的改變,從而影響了電子倍增的過程,并進一步改變或影響了沿面閃絡(luò)的發(fā)展過程。