铝合金析出强化颗粒的微合金化调控

微合金化是目前改善铝合金结构材料综合力学性能最为高效的方法之一。而如何有针对性地选择利用微合金化手段,实现更为有效的微合金化效果,并在更深层次理解微合金化作用机制,是研发高性能铝合金结构材料长期以来所面对的瓶颈与挑战。藉由原子探针技术等多种先进实验测试技术及第一性原理等计算模拟手段,铝合金中的微合金化研究在近期取得了诸多引人注目的成果,对微合金化机理的理解也向更精细的纳米层级乃至原子层级迈进。结合当前国内外有关微合金化铝合金中析出相优化改性的一系列最新进展,分别阐述了3类典型的微合金化机制,包括:作为异质点促进原有析出相形核;提供界面偏聚以提升析出相热稳定性;析出额外的强化相以进一步提升合金强度,并对其进一步的复合微合金化机制做了探讨。文末对铝合金微合金化研究的发展趋势进行了展望。

Tailoring the Strengthening Particles in Aluminum Alloys by Microalloying

Microalloying is one of the most effective approaches to optimize the mechanical properties of aluminum alloys.How to utilize the microalloying effect specifically as well as efficiently,and deeply understand the microalloying mechanism,is a grand challenge for the high-performance aluminum alloys existing for a long period.Based on the recent development of advanced microstructural characterization and computational simulation,the investigations of microalloying mechanism in aluminum alloys have achieved much with a better inspection into nano and atomic scale.This paper briefly reviewed the recent progresses in ageing-hardening microalloyed aluminum alloys aiming to tailor the precipitation behavior,which is generally classified as three main goals:promoting the nucleation of original precipitates as heterogenous nuclei;segregating to precipitate/matrix interface to enhance its stability;creating extra strengthening precipitates.Related multiple microalloying effects were also discussed.At the end,a brief prospect of the microalloyed aluminum alloys in future was proposed.