Powders produced by the method of mechanochemical synthesis for thermal spraying of coatings containing MAX phases

DOI: 10.62564/M4-OB1530

Nataliia Vigilianska, Oleksii Burlachenko, Tetiana Tsymbalista

E.O. Paton Electric Welding Institute, Ukraine


To produce protective coatings containing MAX phases, methods of thin films deposition such as physical vapour deposition and magnetron sputtering are mainly used [1]. Such coatings are only a few microns thick and do not meet the requirements for operation in extreme conditions. Thermal spraying (TS) makes it possible to form coatings several millimetres thick. This work is dedicated to developing compositions and technology of producing powders using commercially available starting materials for thermal spraying of coatings containing MAX phases. The technology of mechanochemical synthesis (MChS) by processing mixtures of powders of the compositions 60.9TiC+39.1TiAl, 75TiAl-25SiC, 68.5(Ti,Cr)C-31.5Al, 82Cr3C2-18Al (wt.%) in a high-energy planetary ball mill was used to produce powders for TS. The compositions were calculated to form the most promising MAX phases: Ti3SiC2, Ti2AlC, Ti3AlC2 and Cr2AlC. The MChS process was performed in air during 1.5 hours. The produced powders products of MChS have a conglomerate structure with particles size <50 μm. In the powder product of MChS of the TiAl-TiC system, the synthesis of MAX phases Ti3AlC2 and Ti2AlC occurs; in the powder of the TiAl-SiC system, Ti2AlC, Ti3AlC2, and Ti3SiC2 are synthesized; in the powder of the (Ti,Cr)C-Al system, Ti2AlC and Cr2AlC are synthesized; in the powder of the Cr3C2-Al system, Cr2AlC is synthesized. In addition to the MAX phases and the phases of the initial components of powder mixtures, the MChS products also contain phases of Ti3AlC, Ti5Si3 and Cr5Al8. It is preferable to use high velocity thermal spraying methods such as HVOF and cold spraying to preserve MAX phases in coatings. The interaction time with oxygen and the high-temperature jet is reduced, and coatings phase composition corresponds to the phase composition of the sprayed powder. In the case of using plasma spraying methods, the synthesis of MAX phases can occur directly during spraying and the formation of the coating layer.

Keywords
MAX phases, Mechanochemical Synthesis, Powders, Thermal Spray, Coatings

Acknowledgments
Not provided

References
[1] N.V. Vihilianska, D.V. Filonenko, A.O. Yushchenko, C. Senderowski, J.-C. Grivel, Thermal spraying of coatings, containing Cr2AlC max-phase (Review), The Paton Welding Journal, 2024. No. 3. P. 24-32.