High Stability, High Enthalpy APS Process Based on Combined Wall and Gas Stabilizations of Plasma (Part 2. Coating Formation and Properties)

This paper includes a brief analysis of properties of different plasmas as well as specifics of coating formation. The analysis showed that high enthalpy N₂-H₂ plasmas could provide a significantly higher heat transfer potential and, consequently, offering a better plasma treatment of spraying particles that in turn results in a better DE and coating properties. The recently developed APS process and torch based on combined wall and gas stabilizations of plasma (C⁺Plasma) was used for the experimental validation of the results of the analysis. The choice was determined by the unique capability of  C⁺Plasma to generate N₂-H₂ plasmas having high enthalpy within 30-70 kJ/g, presently not achievable by other commercial processes. The experimental and 2 years industrial validation results are illustrated by properties of different TBC coating systems sprayed by 120 kW C⁺Plasma integrated systems.