Development of Lifetime Evaluation Method Using Multilayer Coating Chip

Abstract

In order to improve Hall thruster's lifetime performance, A new lifetime evaluation method, lifetime estimation using multilayered coated chips was developed for channel wall erosion rate distribution measurement. This method uses small chips coated with alternate channel wall material and marker. By detecting the marker emission as a signal of erosion progress, this method enables direct and rapid erosion rate distribution measurements. In this study, the capability of this new method for erosion rate distribution measurement was tested and validated. Multilayer coated chips of two kinds using different marker metals were embedded into the acceleration channel wall. The channel-wall erosion rate distribution was then measured. The measured erosion rates were, respectively, 0.90 nm/s and 0.75 nm/s at 2 mm and 4 mm upstream from the channel exit.