EN
In this paper the studies of phase transitions in some material compositions based on Al_{2}O_{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_{2}O_{3}-NiO and Al_{2}O_{3}- ZrO_{2} systems complex phase transitions were observed. More resistant to the conditions of thermal fatigue are coatings containing aluminum titanate Al_{2}TiO_{5} and mullite 3 Al_{2}O_{3}-2 SiO_{2}.