| Abstract Scope |
Co-based superalloys are widely used in jet engine applications due to their excellent resistance to hot corrosion and oxidation. Investment casting is a key manufacturing method for these components, as it allows for the production of complex geometries with high dimensional accuracy. However, surface defects formed during casting can sometimes be unacceptable, necessitating repair welding. This work presents the practical aspects of welding technology for the Co-based superalloy X40, considering both metallurgical aspects and ISO standards requirements. Gas Tungsten Arc Welding (GTAW) was used to apply fill welds on the castings, using Turbaloy 605 filler metal. A thorough analysis, employing both non-destructive and destructive testing methods, indicated that the filler metal is prone to hot cracking in some cases. Based on microstructural observations, the cracking mechanism was identified, and solutions for prevention were proposed.
The authors gratefully acknowledge the funding by National Centre for Research and Development, Poland, under grant POIR.01.01.01-00-0631/18. |