The Influence of Ar/N₂ Plasma Gases on Microstructure of Ceramic Coatings Produced by PS-PVD Method

Abstract

The PS-PVD method is a promising technique for production of ceramic coatings from the vapor phase on gas turbine components. The resulting layers combine benefits of coatings made by the plasma spray method and other methods of Physical Vapor Deposition. The plasma spray process is carried out under reduced pressure (~ 200 Pa) and with the use of a gun applied in the method (the LPPS torch 0C3P). The PS-PVD enjoys many of the benefits of plasma spray methods combined with relatively low production costs and overall better properties. One of the significant costs of coating manufacturing by this method is the use of helium as process gas to generate plasma. The authors attempted to form a ceramic coating from ZrO2, where a mixture of argon and nitrogen in various proportions was used. The resulting layers were analyzed by XRD, LFA, SEM-EDS.

Synthesis of Gd2Zr2O7 Coatings Using the Novel Reactive PS-PVD Process

“…The columns in the deposited ceramic layer were characterized by the presence of additional branches and a large number of open and closed pores between the growing columns and the branches [36]. Additionally, with the increase of the plasma power current, 1800→2000→2200 A, the disappearance of the fine fraction from the material was observed (Figure 1a-c), similar to results obtained in [37]. In the structure of the coating, small spheroidal particles of GZO were visible.…”