FORMATION OF COATINGS ON THE BASIS OF ZIRCONIUM DIOXIDE ON THE ELEMENTS OF SCREENS OF ANTI-ELEMENTARY PROTECTION
The article contains results research of influence of parameters a plasma jet (current, spraying distance, plasma gas consumption) fractional composition of the starting powder and the degree of cooling compressed air on anti-meteoric coating characteristics. We get an anti-meteoric coatings based on zirconia at optimum modes (arc current -600A; spray distance of 110 mm; plasma gas consumption 50 l/min; fractional composition of zirconia powder 3/min; p = 4 bar) with materials utilization rate -62%, total porosity of the ceramic layer -6%. Cubic zirconia modification is the main phase present in the coating after exposure to coating compression plasma flows in a nitrogen atmosphere. The lattice parameter of cubic zirconia is 0.5174 nm. Because of the use of nitrogen as the plasma substance is its interaction with the atoms and zirconium coating is formed from zirconia nitride-ZrN with a cubic crystal lattice (lattice parameter 0.4580 nm). The melting of the surface layer occurs, and the depth of the molten layer, according to a scanning electron microscope is about 8 microns. Crystallized surface layer after exposure to compression plasma flows is characterized by a homogeneous distribution of the elements and the absence of pores formed in the formation of the coating. The structure of the coating represented by a set of large (5 - 7 microns) and small (1 - 2 microns) of zirconium oxide particles sintered together.