Electron-Beam Synthesis of Ceramic-Based Coatings in the Forevacuum Pressure Range

We presented the results of experimental study of the synthesis of zirconium ceramic coatings partially stabilized with yttrium oxide using the electron-beam method in the forevacuum pressure range (1–100 Pa). The experiments were carried out with a forevacuum plasma-cathode electron source operating in the elevated (forevacuum) pressure range. In a high vacuum, at the initial stage of electron-beam heating and evaporation, the dielectric target can be charged to almost the full accelerating potential. This, in turn, negatively affects the efficiency of energy transfer from the electron beam to the irradiated target. The currently developed forevacuum plasma-cathode electron sources operate at a pressure of several to hundreds of Pascals, which is an order of magnitude higher than the operating pressure of hot-cathode or common plasma electron sources. The beam plasma generated in this range of pressure eliminates the charging effect of the dielectric target. Thereby practically all power of the electron beam is transferred to heating, facilitating evaporation of any refractory dielectric materials. The synthesized coatings with a thickness of over 100 µm were studied, and their mechanical and thermal conductive properties were measured.