Future regeneration processes for high-pressure turbine blades
In this paper, new technologies for repairing turbine blades are presented, in which the manufacturing processes and materials mechanisms are incorporated. Since the turbine blades taken into consideration here are components of high pressure turbines, the focus of this paper lies on nickel-based alloys. Depending on the size and form of the defects present on the blades, two procedures can be used for repairing turbine blades: brazing and/or cladding. In one approach, a hybrid repair brazing process was developed, in which the filler metal and the hot gas corrosion protective coating were applied by thermal spraying. Subsequently, a combined brazing and aluminizing process was carried out. In a second approach, a laser cladding process for crack repair was developed wherein single crystalline solidification of the cladding material was carried out.
KeywordsHybrid brazing Laser cladding Single crystal repair Thermal spraying
The work presented here was supported by the German Research Foundation (DFG) within the scope of the sub-project B1 “Near net shape turbine blade repair using a joining and coating hybrid process” and subproject B5 “Single crystalline laser cladding” of the Collaborative Research Centre (SFB 871 “Product Regeneration”). The authors would like to thank the DFG for their support.
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