The storage failure mode and failure mechanism study of high-power klystron

Firstly, the storage failure mode and failure mechanism study of the klystron was carried out, the main failure modes of klystron in storage were summarized, and the failure mechanism and failure reasons of the main failure mode were analyzed. The results of the study showed that the vacuum degree decline is the main reason for the failure in long-term storage of klystron. The vacuum degree decline of tube is due to the residual gas of in seal manufacturing process or the deflation and shell leakage of the tube during the period of storage. Secondly, the generation process of residual gas was studied. At last, a failure sample of long-term storage klystron was analyzed; results showed that the failure mechanism was due to a large number of evaporation the cathode emission material which induced the serious degeneration of cathode, then the cathode emission current reduced and the out power declined. The reason of cathode degradation was vacuum degree decline in long-term storage process, ions back to the cathode surface that caused the huge evaporation of cathode emitting material.