A method of repairing an airfoil, comprising: providing an airfoil with a damaged section; removing the damaged section by machining or cutting an upper section of the airfoil; providing a replacement section configured to mate with an upper surface of the remaining machined or cut airfoil; and characterized by: providing a presintered preform configured to mate with the upper surface of the airfoil and a lower surface of the replacement section wherein the presintered preform comprises a powder mixture of superalloy particles and braze material; inserting the presintered preform between the upper surface of the airfoil and the lower surface of the replacement section creating a stacked airfoil comprising the three mated sections in abutting contact; and resistance brazing the stacked airfoil such that only the braze material of the presintered preform melts and the upper surface of the airfoil and the lower surface of the replacement section remain below the grain boundary temperature of a material of the airfoil, the resistance brazing joining the upper surface of the airfoil to the lower surface of the replacement section, wherein the brazing temperature of the braze material is above the grain boundary melting temperature. providing an airfoil with a damaged section; removing the damaged section by machining or cutting an upper section of the airfoil; providing a replacement section configured to mate with an upper surface of the remaining machined or cut airfoil; and characterized by: providing a presintered preform configured to mate with the upper surface of the airfoil and a lower surface of the replacement section wherein the presintered preform comprises a powder mixture of superalloy particles and braze material; inserting the presintered preform between the upper surface of the airfoil and the lower surface of the replacement section creating a stacked airfoil comprising the three mated sections in abutting contact; and resistance brazing the stacked airfoil such that only the braze material of the presintered preform melts and the upper surface of the airfoil and the lower surface of the replacement section remain below the grain boundary temperature of a material of the airfoil, the resistance brazing joining the upper surface of the airfoil to the lower surface of the replacement section, wherein the brazing temperature of the braze material is above the grain boundary melting temperature. providing a presintered preform configured to mate with the upper surface of the airfoil and a lower surface of the replacement section wherein the presintered preform comprises a powder mixture of superalloy particles and braze material; inserting the presintered preform between the upper surface of the airfoil and the lower surface of the replacement section creating a stacked airfoil comprising the three mated sections in abutting contact; and resistance brazing the stacked airfoil such that only the braze material of the presintered preform melts and the upper surface of the airfoil and the lower surface of the replacement section remain below the grain boundary temperature of a material of the airfoil, the resistance brazing joining the upper surface of the airfoil to the lower surface of the replacement section, wherein the brazing temperature of the braze material is above the grain boundary melting temperature.