铝锂合金动态再结晶行为的研究进展

Research progress on dynamic recrystallization behavior of Al-Li alloy

铝锂合金由于具有低密度、高强度、高损伤容限及良好耐腐蚀性等突出优点,在航空航天领域得到了广泛的应用。铝锂合金在热变形过程中普遍存在动态再结晶现象。本文综述了铝锂合金在不同热加工条件下的三种动态再结晶机制。总结了动态再结晶的研究发展历程以及影响动态再结晶行为的关键因素,包括层错能、第二相粒子、热加工条件与晶粒尺寸。重点阐述了不连续动态再结晶、连续动态再结晶和几何动态再结晶的形核机制与发生条件,详细论述了三种动态再结晶机制对铝锂合金微观组织和力学性能的作用规律。探讨了目前研究中亟待解决的科学问题与技术难题,提出了构建动态再结晶数学模型和调控动态再结晶机制等值得进一步探索的方向。结合电子背散射衍射和透射电子显微镜等表征技术,为学者们更好地理解铝锂合金的动态再结晶提供思路与启发。

Al-Li alloy has been widely used in aerospace field attribute to the advantages of lower density,higher strength,damage tolerance and corrosion resistance.Dynamic recrystallization phenomena exist in Al-Li alloy during hot deformation.This paper overviews the dynamic recrystallization behavior occurring in hot processing of Al-Li alloy.The research history of dynamic recrystallization is summarized,together with the key factors that influencing the dynamic recrystallization processes including stacking fault energy,grain size,hot processing conditions and secondary particles.The nucleation mechanisms and conditions of discontinuous dynamic recrystallization,continuous dynamic recrystallization and geometric dynamic recrystallization are depicted and analyzed respectively,followed by a discussion on the effects of the forward three dynamic recrystallization mechanisms regarding the mechanical properties and microstructure.Ultimately,the unsolved and challenging scientific and technological issues are highlighted with some aspects desiring further exploration.It is feasible to provide ideas and inspiration for scholars to better comprehend dynamic recrystallization mechanisms during the hot deformation of Al-Li alloy with the assistance of electron backscatter diffraction and transmission electron microscopy characterization methods.