Peculiarities of operation of tubular thermocathode heated by laser radiation

摘要

Model of cathode processes for tubular thermocathode of a laser arc plasmatron which takes into account an auxiliary heating of the cathode working surface by a passing laser beam is offered. A detailed computer modeling of cathode processes for the above-mentioned cathode was made. It is shown that the auxiliary laser heating can provide effective control of the cathode processes, and, consequently, characteristics of plasma in the near-cathode region. The design of the cathode unit of the laser-arc plasmatron for the powder surfacing was based on the results. Experimental investigations of plasmatron demonstrated high stability of operation and high service life of the designed tubular electrode.