Thermally Sprayed Nickel-Based Repair Coatings for High-Pressure Turbine Blades: Controlling Void Formation during a Combined Brazing and Aluminizing Process

Turbine blades must withstand severe loading conditions and damage can occur during operation due to heat, pressure, foreign objects hot gas corrosion, despite the protective coatings applied onto turbine blades. Instead of replacing damaged components, maintenance, repair overhaul are key extend total service life. Besides welding, by brazing is an established process in industry involves many individual steps that often require a high degree manual work. In present study, hybrid joining coating technology was developed shorten state-of-the-art chain for repairing With this approach, coating, which consists filler metal, corrosion layer aluminum top layer, atmospheric plasma spraying. The coated blade then undergoes heat-treatment so aluminizing carried out simultaneously. Due diffusion segregation processes, pores heat-treated coating. full factorial design experiment performed reduce microstructure investigated optical- scanning electron microscopy (SEM), impact parameters on resulting discussed.