Marks on Single-Crystal Copper Cathodes after Short-Pulse Voltage Impact on Vacuum Gaps

The objects of experimental research were vacuum gaps (VGs) with electrochemically polished copper single-crystalline cathodes. VGs were exposed to short (20 ns) voltage pulses of high (200 kV) and low (25 kV) voltage amplitudes. The results indicate that plastic phenomena occurring inside the electrode material with the participation of linear defects of crystal structure play a significant role in the development of vacuum breakdown.