铝锂合金纳米析出相对力学性能各向异性影响的研究进展

Research progress on effect of nano-precipitates on mechanical property anisotropy of Al-Li alloys

铝锂合金具有低密度、高比强度、高损伤容限和优良耐腐蚀性等突出优点,在航空、航天等领域得到了广泛关注。但铝锂合金存在强烈的力学性能各向异性问题,制约了其进一步的工程应用。研究发现,各类纳米析出相是影响合金各向异性的重要因素。本文概述了铝锂合金中纳米析出相对力学性能各向异性的影响。阐述了含Cu、Li时效强化相对各向异性的直接作用,论述了预测合金力学性能各向异性的数学预测模型;讨论了含Zr、Mn弥散相对各向异性的间接作用;总结了合金成分调控、变形工艺优化和时效制度优化等多种降低合金各向异性的有效方法,并提出了未来研究中值得进一步探索的难点、重点问题。结合当前国内外研究现状,为学者们更好地理解铝锂合金纳米析出相与力学性能各向异性间的关系提供新的思路与启发。

Al-Li alloys have been extensively used in the aerospace field attributed to the advantages of low density,high specific strength,high damage tolerance and superior corrosion resistance.However,these alloys exhibit the strong mechanical property anisotropy,which restricts further engineering applications.The investigation results show that nano-precipitates are key factors affecting the anisotropy.In this paper,the effect of nano-precipitates on mechanical property anisotropy of Al-Li alloys were reviewed.The direct role of(Cu,Li)-containing aging reinforcing phases on anisotropy was expounded emphatically,as well as the associated numerical prediction models.The indirect effect of(Zr,Mn)-enrich phases on anisotropy was also systematically analyzed.Then,several effective methods to reduce anisotropy,such as alloy composition control,deformation process optimization and aging treatment optimization,were summarized.Ultimately,the unsolved and challenging scientific issues are highlighted with some aspects desiring further exploration.It is feasible to provide ideas and inspiration for scholars to better comprehend the relationship between nano-precipitates and mechanical property anisotropy of Al-Li alloys based on the current domestic and internation research status.