Creep performance evaluation considering the operating environment of gas turbine blades with rejuvenation maintenance

The blade is the main component of a gas turbine and operates in a harsh high-temperature environment. Nickel-based super alloys with excellent performance at high temperatures are mainly used for blades, and inspection and replacement are performed based on the manufacturer's standards. In previous research, microstructure analysis and mechanical strength evaluation were performed for blades that were used in domestic operating environments and exceeded their service life based on the manufacturer’s standards, and the optimal rejuvenation conditions were derived. In this study, to verify the derived rejuvenation conditions for gas turbine blades, we evaluated the creep durability according to the aging time using commercial gas turbine blades of new and rejuvenated products. The size and volume fraction of γ′ and MC decomposition that affect creep durability were measured through microstructure analysis, and the test results were evaluated.