Thermal Resistance and Phase Transitions Studies for Some composite Materials Based on Al$\text{}_{2}$O$\text{}_{3}$

In this paper the studies of phase transitions in some material compositions based on Al$\text{}_{2}$O$\text{}_{3}$ caused by high-temperature processes are presented. These material compositions may be used to high-temperature resistant plasma sprayed coatings. The occurring phase transitions are studied by X-ray diffraction methods. Phase transitions and thermal resistance for studied oxide systems are different. In the coatings from the materials belonging to Al$\text{}_{2}$O$\text{}_{3}$-NiO and Al$\text{}_{2}$O$\text{}_{3}$- ZrO$\text{}_{2}$ systems complex phase transitions were observed. More resistant to the conditions of thermal fatigue are coatings containing aluminum titanate Al$\text{}_{2}$TiO$\text{}_{5}$ and mullite 3 Al$\text{}_{2}$O$\text{}_{3}$-2 SiO$\text{}_{2}$.