Formation of Ni–Cr–Al–Ta–W–Hf–Y Composite Heat-Resistant Coatings on Nickel Superalloys

The formation of a multicomponent composite heat-resistant Ni–Cr–Al coating alloyed with tantalum, tungsten, and hafnium using the methods of vacuum carburizing, gas circulation aluminizing, vacuum plasma cathode deposition, and thermobaric treatment is considered. The laws of formation of the chemical composition, structure, and state of stress in a Ni–Cr–Al–Ta–W–Hf–Y composite coating are established. Yttrium is shown to play a positive role as a deoxidizer of condensate coatings, and thermobaric treatment is found to decrease the microporosity and the grain size in the deposited composite coating.