Research for development of industrial coating equipment based on an electrothermal launcher

Investigations of powder material microparticle acceleration in a pulsed electrothermal launcher made it possible to solve some problems related to the development of an industrial coating equipment. One of those problems is the increase of the life time of the launcher discharge units. Study of erosion wear of launcher electrodes was performed on a specially constructed experimental bench. The shape of electrodes made from WNiFe alloy was chosen so that the erosion wear was decreased by more than an order of magnitude (from 0.36 mg per a discharge down to 0.01 mg per a discharge). That resulted in the increase of the launcher operational time to several working shifts. For the ablation wear of the discharge unit dielectric walls to be studied two models have been developed. The first one allows us to determine heat flux of the discharge plasma in argon media. The other one describes the process of that flux propagation in dielectric walls. The experimental determination of the ablation wear was carried out on a launcher prototype with corundum bushings. The analysis of calculated and experimental results has .shown that for normal operational regimes the typical ablation value was about 1 mg/shot.