An embodiment of a turbine assembly includes, among other possible things, a first component including a first component surface, a second component including a second component surface spaced apart from the first component surface, and a brush seal disposed between the first component and the second component. The brush seal includes, among other things, a first bristled region extending in a first direction from a backing plate, and sealingly engaging one of the first component surface and the second component surface. At least one of the backing plate and the first bristled region includes a nickel-based superalloy material having at least 40% of a Ni3(Al,X) precipitate phase, X being a metallic or refractory element other than Al.