The mechanism of surge current failures has not been understood completely yet, and different hypotheses were discussed in relevant literature. These include a sustained scintillation
breakdown model [1-3]; electrical oscillations in circuits with a relatively high inductance [4-6];
local overheating of the cathode [5, 7, 8]; mechanical damage to tantalum pentoxide dielectric
caused by the impact of MnO2crystals [2, 9, 10]; or stress-induced-generation of electron traps
caused by electromagnetic forces developed during current spikes [11].
https://nepp.nasa. …20Solid%20Tantalum.pdf