Development and suggestions of surface mechanical treatments for aero-engines

Fatigue failure of critical components in aero-engines will compromise the flight safety of aircraft once it occurs. Fatigue failure mainly initiates from defects formed by metallurgical, processing, and environmental factors in the surface and subsurface layers of components, and then propagates under accumulated service damage, resulting in sudden fracture without obvious macroscopic plastic deformation, which may lead to severe risks. Surface mechanical treatment employs surface work hardening to introduce a micro-deformed layer on metallic components. Without impairing the bulk properties of the metal, it significantly improves the durability performance of metallic structures, such as fatigue resistance and stress corrosion cracking resistance, making it particularly suitable for long-life service of aero-engine components under high-performance operating conditions. In response to the development requirements of advanced aero-engines, this paper compares the state-of-the-art of typical surface mechanical treatments worldwide, puts forward development suggestions including enhanced structural adaptability, medium optimization, intellectualization, and integration into strength design, and proposes supporting strategies to ensure the rapid development and effective application of surface mechanical treatment. It provides decision-making references and technical support for the development of new-generation aero-engines and surface mechanical treatments.