Prituliak A. Structure formation and ways of functional properties improving for thermal barrier gas-thermal coatings from ZrO2 on Ti-Al alloys

Investigations object - dependence of thermal barrier coatings properties from properties of feedstock powders and structure of the coating. The purpose of the work is - development of zirconia-based thermal barrier coatings with advanced properties for titanium alloys and titanium aluminides details protection. Investigations methods - thermal analysis, x-ray investigations, adsorption method of specific surface definition - BET, electronic microscopy, gradient method of thermal conductivity definition, microindent. It was shown that due to s inheritance by the coating of fine feedstock powder structure, mechanical properties could be improved and thermal conductivity of zironia thermal barrier coatings - reduced. Interconnection of diffusion and oxidation properties were discovered in thermal barrier coatings with TiAlCr bond layer on the titanium and Ti-Al based substrates. It was shown that behavior of TiAlCr coatings during high-temperature oxidation depends on substrate composition; witch, inturn, determined diffusion processes character on the border coating-substrate. Dependence of velocity and degree of TiAlCr substrate oxidation from microstructure of outer ZrO2 layer was shown. It was offered the model of porous coating thermal conductivity, taking into account not only relative pores volume, but their size. On Antonov ANTK certification tests of developed coating were carried out. Tests showed that developed coating had enlarged work time comparing to the coating from commercial powder.