Advances in Tribology of Aero-Engine Materials

Tribological problems are inherent in mechanical systems and have significant implications for their performance and reliability. The complicated aero-engine requires special attention to the friction and wear as the heart of the aircraft. Effective control of material tribological behavior is a potent strategy for mitigating wear in aero-engines. This approach not only minimizes the tribology damage but also inhibit precision degradation, ultimately enhancing the long-term stability and reliability of aero-engines. This review offers an introduction of the critical frictional couples found in a classical third-generation turbine engine. These frictional couples span the spectrum from the engine's low-temperature sections, such as the air inlet and fan, through to the high-temperature sections, including the intermediate casing, compressor, combustion chamber, and turbine, among others. The operation condition, tribology mechanism and failure severity of these wear components are introduced. The selection of the four key research areas in aero-engine tribology was based on the failure analysis of the aero-engine. They are the high-speed rubbing of blade tip against seal coating, the rolling contact fatigue and sliding damage of the main shaft bearing, the fretting damage of titanium alloy blade, and the friction wear and bench test of graphite of dynamic sealing device. All these research areas are reviewed from various perspectives, including the evolution of material properties related to tribology behavior, wear mechanisms, wear resistance, and surface modifications. The research roadmap for the aero-engine materials tribology is proposed. Initially, the wear failure characteristics of the damaged components should be reproduced by tribology test from the material-level tribology test. Subsequently, the improvement in friction reduction and wear resistance of the materials would be achieved by the investigation on wear mechanism. Finally, the tribology performance of the optimized material is validated on the simulated condition tribological test rigs. Furthermore, the development trends in the research of aeroengine materials tribology are briefly outlined, including wide-temperature lubrication, corrosion-wear interactions, and material tribology databases due to the higher demands on material performance for the next-generation aero-engines. © 2023 Science Press. All rights reserved.