Nonvacuum Surfacing of Protective Coatings Using a Low-Energy Electron Beam

Abstract

The results of electron-beam surfacing in air of protective coatings by a low-energy (120 keV) electron beam produced by an electron gun with a plasma emitter are presented. The gun is mounted on an industrial robotic manipulator KUKA, which allows the electron beam to be moved to the atmosphere along a given path without electromagnetic sweep. The combined (self-propagating high-temperature synthesis and electron-beam surfacing) method for obtaining coatings from reaction mixtures of TiO₂: 2.1C and TiO₂: 0.3Cr₂O₃: 3.3С is implemented using this setup. The optimum composition of the reaction mixtures and the deposition regimes are determined by thermodynamic modeling using the TERRA program. The obtained coatings with a thickness of 120–200 μm have a microhardness of 12 GPa. The coatings and the transition layer are established to have good heat resistance up to 900°C. Noticeable changes in the weight characteristics of coatings occur at above 1000°C.