Multinary alloys, in particular for use as coatings, if appropriate in combination with other types of layers, for components which are exposed to high temperatures and corrosive gases. The alloys are of the general form: Al--Ni--Ru-M, where at least one B2 phase is present, the aluminum content being in the range from 26 60 atomic percent and where M may be one or more metals and/or semimetals selected from the group consisting of: precious metal, transition metal, rare earths, semimetal. Multinary alloys of this type are very stable with respect to oxidation, have a low thermal conductivity and in particular have similar coefficients of thermal expansion to superalloys, which are usually used as substrates for protective coatings of this type in gas turbine components.