Operational testing of self-heated cathode made from compacted TiN powder

The results of tests of a self-heated hollow cathode made by magnet-pulse pressing of the mixture of TiN (90 %) and Ti (10 %) powders with further high-temperature annealing and fusing during operation of the compact as a cathode in high-current (10 - 45 A) discharge are presented. It was found that the rate of the cathode mass loss during operation in Ar/N2 mixture made 2.3*10-7 g/C. The possibility of the cathode use for oxygen-argon plasma generation at separated gas feeding (argon – through cathode cavity, and O2 – to anode area of discharge) was shown. Testing of massive tubular cathodes with the increased thickness of the wall (up to 2.5 mm) and large inner diameter (up to 12 mm) possessing an enhanced resource (300 - 500 h) was carried out.