Abstract: A heating apparatus and method for welding a superalloy article. The apparatus and method of this invention provide for pre-weld and post-weld heat treatments to be performed on an article within the same enclosure in which the welding operation is performed. The apparatus accurately controls the temperature of the component to be welded throughout the temperature treatment profiles with the use of means for welding the article, means for heating the article, and means for sensing the article temperature. The apparatus also works in conjunction with a memory storage device that stores appropriate pre-weld and post-weld heat treatment temperature profiles and a welding temperature profile for the article.

Abstract: An apparatus and method for welding a superalloy article. The apparatus generally entails an enclosure adapted for containing a superalloy article, a polarity-reversing plasma transferred arc welder apparatus for welding a localized region of the article, an induction coil for heating the localized region, and elements for sensing and controlling the temperature of the localized region. The induction coil is placed in close proximity to the localized region of the article so that the temperature of the localized region is largely determined and quickly altered by the output of the coil. The polarity-reversing plasma transferred arc welding apparatus is operated at very low currents of not more than forty-five amps, so that the welding apparatus has only a secondary heating affect compared to the induction coil.

Abstract: A method for repairing a turbine engine airfoil having an environmental resistant coating on a outer wall surface includes selecting and masking a discrete portion of the airfoil outer wall surface to protect the coating on the selected discrete portion, thereby providing a masked outer wall surface and an unmasked outer wall surface. The coating is removed from the unmasked outer wall surface, the maskant is removed, and the airfoil is repaired.

Abstract: A method for repairing a damaged tip of a turbine engine member, for example a tip of a high temperature operating turbine blade, having a designed length and an environmental resistant coating at least on an outer wall of the member and extending at least onto the tip, includes removing the damaged tip without first removing coating, on a wall adjacent the tip. This provides a preform end surface to which is bonded a replacement tip material having a second length greater than the designed length. Then a portion of the replacement tip material is removed to provide the member with a repaired member tip and of substantially the designed length while retaining the coating on the wall adjacent the repaired tip.