Research Status of Additive Repairing Technologies for Nickel-Based Cast Superalloy Blades

Cast nickel-based superalloys are widely used in high-temperature parts such as gas turbine and aeroengine blades. During long-term operation, local damages of blades often occur, but the manufacturing cost is very high. If the local damage can be recovered by additive repairing, the cost and manufacturing cycle would be greatly reduced, and the resources would be saved, which has great social benefits and market value. In view of the service circumstances and failure modes of nickel-based cast superalloy blades for gas turbines and aeroengines, combined with the composition, microstructures and performances of nickel-based cast superalloy, the types, characteristics and formation mechanism of cracks in the repair of additive were analyzed systematically, the primary influencing factors of various cracks were described, and the reduction or avoiding of cracks were summarized from the two aspects of additive technology and material. In addition, the advantages and disadvantages of different methods and the possible research hotspots in the future were analyzed.