Al-Zn-Mg系铝合金的微合金化研究进展

Research progress in microalloying of Al-Zn-Mg series aluminum alloys

Al-Zn-Mg系铝合金作为一种轻质高强合金在航空航天和交通等领域有着重要的应用。获得更高的力学性能以及更优的耐腐蚀性能是Al-Zn-Mg系合金的发展方向,因此需要进一步优化其微观组织。在合金成分和热处理制度调控空间有限的情况下,微合金化成为该合金性能改善的一种重要手段。本文简要总结了微合金化元素对Al-Zn-Mg系铝合金力学性能、热加工行为及耐腐蚀性能的影响,重点关注了微合金化元素在不同工艺阶段下形成的第二相颗粒能有效细化晶粒并强烈阻碍位错运动;讨论了热加工变形过程中钉扎晶界及亚晶界、抑制回复再结晶的作用;阐述了提高合金耐腐蚀性能方法的内在机理。最后对Al-Zn-Mg系铝合金微合金化的研究方向进行展望,深入理解微合金化元素间、主微合金元素间的相互作用机理,实现微合金化元素的精准、精确投放将是未来主要的研究内容之一。明确微合金化元素在热加工过程中对变形组织及位错组态的调控作用将对提高合金耐腐蚀性能提供借鉴。

Al-Zn-Mg series aluminum alloys have important applications in aerospace,transportation etc,for their excellent properties of low density and high strength.Further optimizing the microstructure to obtain higher mechanical properties and better corrosion resistance is the development direction of Al-Zn-Mg alloys.Microalloying has become an important means of improving the properties of aluminum alloys,owing to the limited space for alloy composition optimization and heat treatment processes improvement.The effects of microalloying elements on the mechanical properties,hot deformation behavior and corrosion resistance of Al-Zn-Mg alloys were briefly summarized,focusing on the different effects of the second phase particles formed by microalloying elements in different process stages,such as effectively refine grains and strongly hinder the movement of dislocations.The effects of pin grain boundaries,sub-grain boundaries and inhibiting recrystallization during hot deformation were discussed.The internal mechanism of improving the corrosion resistance of the alloy was explained.In addition,the further research direction of microalloying of Al-Zn-Mg aluminum alloy was prospected,understanding the interaction mechanism of microalloying elements and dual alloying-microalloying elements to realize the precise and accurate addition of microalloying elements will be one of the main research contents in the future.Clarifying the regulation effect of microalloying elements on deformation structures and dislocation configurations during hot working will provide a reference for improving the corrosion resistance of alloys.