Electron-beam physical vapor deposition with decreasing plasma density

Abstract

In this paper, through an in-depth analysis and study of electron-beam physical vapor deposition accompanied by a decrease in plasma density, it has many interesting features compared to atmospheric plasma spraying (APS), including non-linear observation of deposition, high deposition rate, and microstructural flexibility, with the results show that a small number of compositional differences in the binder layer materials of different systems have no significant effect on the macroscopic morphology, porosity, and microhardness of the plume ceramic layer, but affect the bond strength, high-temperature oxidation resistance and thermal shock resistance of the coating, while all three properties of the coating are superior. The bonding layer affects the bond strength of thermal barrier coatings by influencing the nucleation and growth process of columnar crystals, resulting in different columnar crystal densities in the thermal barrier coating systems with different bonding layers. As the original grain size increases, the force on the particles in the plasma flow changes, the number of vaporized particles entering the centre of the flame flow increases, and the powder vaporization efficiency increases. High gas-phase concentration agglomerated crystals grow fully dense layer thin, columnar crystals slender and uniform; low gas-phase concentration agglomerated crystals are difficult to grow, columnar crystals will preferentially grow on the surface of the liquid phase and spherical particles, columnar crystals are short and thick.