Structure formation during gas-detonation spraying of coatings from composite powders TiAl$_3$ and Ni$_3$Al

This paper considers the mechanisms of structure formation during gas detonation spraying of coatings of TiAl$_3$ and Ni$_3$Al intermetallic compounds produced under equilibrium and nonequilibrium synthesis conditions. The coating sprayed from TiAl$_3$ has the same phase composition as the initial powder, regardless of the synthesis conditions. During spraying of Ni$_3$Al, the structure of the coating also does not depend on the synthesis conditions and consists of two phases – Ni$_3$Al and NiAl, with the crystal structure varying along the coating thickness. Comparative impact abrasion tests of the coatings showed advantages of TiAl$_3$ coatings over coatings based on Ni$_3$Al and titanium diboride.