飞机起落架用超高强度不锈钢的研究及应用进展

本文结合飞机起落架的设计理念,梳理了飞机起落架用超高强度钢及高强不锈钢的应用及发展历程,重点阐述了典型超高强度不锈钢的成分、组织和力学性能以及强韧化机理。建议通过材料热力学动力学计算创新设计新的超高强度不锈钢钢种;提出新型超高强度不锈钢的组织设计,将更关注多类型或高密度的共格析出强化以及高力学稳定性残余奥氏体的强韧化作用机制;最后指出采用最新的一些加工工艺技术,如等温多向锻造工艺技术,可显著提高超高强度不锈钢的综合力学性能。

Research and application progress in ultra-high strength stainless steel for aircraft landing gear

Based on the design concept of aircraft landing gear, the recent achievements in research and development on both ultra-high strength steels and ultra-high strength stainless steels (UHSSS) for the landing gear in aircraft were reviewed. The composition, microstructure and mechanical properties of typical commercial UHSSS grades that were produced and used were also summarized. It was then proposed that the future research on UHSSS with the improved combination of strength and toughness should focus on designing both composition and processes of new UHSSS grades by using the up-to-date material thermodynamic and kinetic calculations, particular attention should be paid to microstructural designing on either high density coherent or multi-type nanosized precipitation and the deliberate tailoring of retained austenite with enhanced mechanical stability for toughening;both of them could contribute to the strengthening and toughening of UHSSS. Finally, the updated hot working technology was put forward, the isothermal multi-direction forging, which could significantly improve the comprehensive mechanical properties of UHSSS.