Progress in mechanical property testing and characterization technologies of aero-engine materials for long-life design

As high bypass ratio turbofan aero-engines develop towards longer service life and higher reliability, the mechanical property testing and characterization of materials have become the key to ensuring their long-term reliable operation. This paper systematically reviews the progress in the testing technologies, damage characterization and service life prediction of aeroengine materials for long-life design, mainly focusing on three typical scenarios: very-high cycle fatigue of rotor blade materials, long-term high-temperature creep of turbine hot-end components and fatigue crack characterization of real process defect-limited-life materials. It introduces the application of technologies such as very-high-frequency vibration fatigue based on electromagnetic vibration tables, creep measurement based on DIC methods, creep life prediction based on segmented models/physical mechanisms and in-situ fatigue based on SEM/CT in this field. In the future, it is necessary to further study the physical mechanisms of very-high cycle fatigue crack initiation, long-life creep rate stress dependence and microstructure evolution and real process defect damage evolution of aeroengine materials. Meanwhile, it is necessary to further promote intelligent life prediction models based on transfer learning, reinforcement learning, attention mechanisms and so on to achieve an integrated evaluation of the microstructure-performance-life of aero-engine components, in order to meet the continuous challenges brought by future aero-engines.