Properties, Peculiarities and Applications of Powder Coatings Formed by Multi-Chamber Detonation Sprayer

The paper describes the properties of Ti, Nickel-based, and Al2O3 powder coatings obtained through a new method of powder acceleration which allows to achieve the powder velocity of 1400m/s. The Ti-based coatings thus formed have nanocrystal and amorphous structure with nanodispersed ceramic compounds inclusions, and show the hardness of up to 16GPa, high plasticity and adhesion strength. The Nickel-based alloy coatings display both nanocrystal and amorphous structure. In ceramic Al2O3 coatings high spraying velocity allows filling in the space between the deformed oxide particles (about 0.053 microns in size) by nanocrystal and amorphous phases; thus, the coatings acquire a high degree of plasticity retaining high hardness of 1320 HV0.3 with the porosity below 0.5%. The Al2O3 coatings were tested and found effective for covering the surface of porous metal matrixes in burners.