iron based superalloy cobalt based superalloy or a nickel based superalloy an appropriate repair material can be selected according to the alloy material appropriate braze materials and methods for such alloys are disclosed in commonly owned u s pat no 6 464 128 which is hereby incorporated by reference in its entirety for example in one embodiment the repair material is a braze material comprising a powder of a first alloy component and a powder of a second alloy component each component having different solidus temperatures the repair material that is later formed as a melted mixture of the first powder and the second powder has a solidus temperature less than that of a shroud material that forms a repair region on the assembly 20 such as the joinder between the repair cover 34 and spoolie boss 32 and the repair cover 34 and the plenum casting 25 and outer housing 26 the repair material powders selected for use with cobalt base replacement elements 34 32 and the housing 26 materials are different from those selected for nickel base assemblies 20 and elements 34 32 in one embodiment the sheet material of the repair cover 34 is a cobalt base alloy known as mar m509 which has a nominal composition in weight percent comprising about 23 5 percent chromium about 10 weight percent nickel about 7 percent tungsten about 3 5 percent tantalum about 0 2 percent titanium about 0 4 percent zirconium about 0 6 percent carbon no more than about 2 percent iron the balance cobalt and impurities additionally in this embodiment the braze repair.