Assessment of microstructure and property of a service exposed turbine blade made of K417 superalloy

2017 2nd International Seminar on Advances in Materials Science and Engineering

Wang, Bingxue^1 ; Wang, Chan^1 ; Shi, Duoqi^1 ; Yang, Xiaoguang^1 ; Li, Zhenlei^1

School of Energy and Power Engineering, Beihang University, Beijing, China^1

关键词: Coarsening behavior;    High temperature;    Metallographic observations;    Microhardness tests;    Microstructural features;    Microstructure and properties;    Nickel- based superalloys;    Service safeties;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/231/1/012084/pdf
DOI  :  10.1088/1757-899X/231/1/012084

来源: IOP

【 摘 要 】

In this paper, a turbine blade made of K417 nickel-based superalloy after service for 600 hours was investigated, the microstructural features were identified through metallographic observation, the size of γ′ precipitates was adopted to quantitatively characterize the coarsening behavior, decomposition of primary carbides was also analyzed. In addition, micro-hardness tests were conducted on the turbine blade. The results indicated that size of γ′ precipitates in the tip region of the blade had a small increase, the decomposition of primary carbides did not occur. Meanwhile, the little reduction in micro-hardness in the tip section was found, which was caused by the coarsening of γ′ precipitates. To sum up, the service induced damage of the turbine blade after service for 600 hours was slight, the degeneration in the tip region was relatively obvious due to high temperature, the result is of great significance to evaluating the service safety of service exposed turbine blades.