Repair and rejuvenation procedures for aero gas-turbine hot-section components

Abstract

AbstractAbstractThe general procedures for repairing aero gas-turbine hot-section components are described. A number of examples are given in order to illustrate particular repair processes: (i) the welding of nozzle guide vanes made from high–strength, nickelbase alloy, demonstrating the effect of microstructural refinement and welding techniques; (ii) the brazing of similar nozzle guide vanes, with emphasis on the advantages of using a halide cleaning process and of modifying the braze alloy by adding a powder having a composition close to that of the parent metal; (iii) the use of an improved coating system to upgrade components; (iv) the possibility of using MCr AlY coatings applied by low–pressure plasma spraying; and (v) hot isostatic pressing as a method of restoring creep life.MST/103