Influence of Mechanical Activation on the Evolution of TiSiCN Powders for Reactive Plasma Spraying

Abstract

In modern materials science and surface engineering, reactive plasma spraying (RPS) holds a key position due to its ability to create high-quality coatings with unique properties. The effectiveness of this process is largely determined by the physicochemical characteristics of the initial powder materials. This study examines the effects of mechanical activation for two compositions in the TiSiCN system and their impact on the quality and performance characteristics of RPS-produced coatings. It is shown that mechanical activation induces significant changes in the crystalline structure of the powders, reducing their particle size and increasing their specific surface area, thereby enhancing the reactivity of the materials during mechanochemical reactions. These changes contribute to the formation of dense and durable coatings with improved hardness and thermal stability. Thermogravimetric analysis (TGA) results confirm that the powders retain stable thermal properties and exhibit resistance to oxidation and decomposition. X-ray structural analysis reveals multiphase structures, including TiC, SiC, and TiCN, with the TiCN phase playing a key role in ensuring coating hardness. Additionally, SEM analysis showed that the TiSiCN-2-2 coating possesses a denser and more homogeneous structure with minimal pores and microcracks, providing superior mechanical strength and wear resistance compared to TiSiCN-1-2. Cross-sectional micrographs further revealed that the TiCN + Si coating has a greater average thickness (39.87 μm) and more uniform distribution compared to Ti + SiC (35.48 μm), indicating better application control and a more homogeneous material structure. Mechanical activation significantly influences the properties of powders, allowing for the determination of optimal parameters for RPS, which is a highly efficient method for creating coatings with unique performance characteristics.