Simultaneous improvement of strength and ductility of Al-2.9Cu-0.8Li alloy: Through addition of Sc and Ti and low-temperature pre-aging treatment

IF 6.2 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Materials Characterization Pub Date : 2026-04-01 Epub Date: 2026-02-16 DOI:10.1016/j.matchar.2026.116165

Wei Zhou , Zhen-zhen Liu , Wen-bin Sun , Hao Cheng , Bang-guo Wu , Tian-le Liu , Dan-yang Liu , Jin-feng Li

{"title":"Simultaneous improvement of strength and ductility of Al-2.9Cu-0.8Li alloy: Through addition of Sc and Ti and low-temperature pre-aging treatment","authors":"Wei Zhou , Zhen-zhen Liu , Wen-bin Sun , Hao Cheng , Bang-guo Wu , Tian-le Liu , Dan-yang Liu , Jin-feng Li","doi":"10.1016/j.matchar.2026.116165","DOIUrl":null,"url":null,"abstract":"<div><div>The influence of trace Sc and Ti additions on the microstructure evolution and mechanical properties of Al-2.9Cu-0.8Li alloy was investigated. Furthermore, the mechanical performance was enhanced through the introduction of a low-temperature pre-aging treatment. The results indicated that the combined addition of Sc and Ti combined with low-temperature pre-aging treatment ultimately yields an excellent combination of mechanical properties, including an ultimate tensile strength (UTS) of 449.7 MPa, yield strength (YS) of 368.1 MPa, and elongation (EL) of 14.6%. The Sc and Ti elements were found to preferentially co-precipitate with Zr during solidification, forming Al<sub>3</sub>(Sc, Zr, Ti) particles that act as nucleation sites to refine the alloy's grain structure. During recrystallization, these particles inhibit grain boundary migration, thereby contributing to enhanced grain refinement. During the artificial aging process, the Al<sub>3</sub>(Sc, Zr, Ti) particles acted as nucleation sites to promote the precipitation of T<sub>1</sub> and S phases, while reducing the width of precipitate-free zones (PFZs) at grain boundaries (GBs). Additionally, Sc and Ti solute atoms were verified to exhibit strong interactions with clusters such as Va, Cu-Va, and Mg-Va, significantly accelerating the precipitation of the S phase while suppressing the formation of the θ’ phase. Furthermore, a low-temperature pre-aging treatment creates favorable nucleation conditions for the T<sub>1</sub> phase, increasing its number density and promoting a more uniform distribution. These factors collectively contribute to the improved strength and ductility of the studied Al-Cu-Li alloy.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"234 ","pages":"Article 116165"},"PeriodicalIF":6.2000,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Materials Characterization","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1044580326002020","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2026/2/16 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"MATERIALS SCIENCE, CHARACTERIZATION & TESTING","Score":null,"Total":0}

引用次数: 0

Abstract

The influence of trace Sc and Ti additions on the microstructure evolution and mechanical properties of Al-2.9Cu-0.8Li alloy was investigated. Furthermore, the mechanical performance was enhanced through the introduction of a low-temperature pre-aging treatment. The results indicated that the combined addition of Sc and Ti combined with low-temperature pre-aging treatment ultimately yields an excellent combination of mechanical properties, including an ultimate tensile strength (UTS) of 449.7 MPa, yield strength (YS) of 368.1 MPa, and elongation (EL) of 14.6%. The Sc and Ti elements were found to preferentially co-precipitate with Zr during solidification, forming Al₃(Sc, Zr, Ti) particles that act as nucleation sites to refine the alloy's grain structure. During recrystallization, these particles inhibit grain boundary migration, thereby contributing to enhanced grain refinement. During the artificial aging process, the Al₃(Sc, Zr, Ti) particles acted as nucleation sites to promote the precipitation of T₁ and S phases, while reducing the width of precipitate-free zones (PFZs) at grain boundaries (GBs). Additionally, Sc and Ti solute atoms were verified to exhibit strong interactions with clusters such as Va, Cu-Va, and Mg-Va, significantly accelerating the precipitation of the S phase while suppressing the formation of the θ’ phase. Furthermore, a low-temperature pre-aging treatment creates favorable nucleation conditions for the T₁ phase, increasing its number density and promoting a more uniform distribution. These factors collectively contribute to the improved strength and ductility of the studied Al-Cu-Li alloy.

查看原文本刊更多论文

同时提高Al-2.9Cu-0.8Li合金的强度和塑性：通过添加Sc和Ti和低温预时效处理

研究了微量Sc和Ti添加量对Al-2.9Cu-0.8Li合金组织演变和力学性能的影响。此外，通过引入低温预时效处理，力学性能得到了提高。结果表明，Sc和Ti复合添加并结合低温预时效处理，最终获得了优异的综合力学性能，其极限抗拉强度（UTS）为449.7 MPa，屈服强度（YS）为368.1 MPa，伸长率（EL）为14.6%。在凝固过程中，Sc和Ti元素优先与Zr共析出，形成Al3（Sc, Zr, Ti）颗粒，作为形核位点，细化合金的晶粒组织。在再结晶过程中，这些颗粒抑制晶界迁移，从而促进晶粒细化。在人工时效过程中，Al3（Sc, Zr, Ti）颗粒作为形核位点促进了T1和S相的析出，同时减小了晶界处无析出带的宽度。此外，Sc和Ti溶质原子与Va、Cu-Va和Mg-Va等团簇表现出强烈的相互作用，显著加速了S相的析出，同时抑制了θ′相的形成。此外，低温预时效处理为T1相的形核创造了有利的条件，增加了其数量密度，使其分布更加均匀。这些因素共同提高了所研究的铝铜锂合金的强度和延展性。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Materials Characterization 工程技术-材料科学：表征与测试

CiteScore

7.60

自引率

8.50%

发文量

746

审稿时长

36 days

期刊介绍： Materials Characterization features original articles and state-of-the-art reviews on theoretical and practical aspects of the structure and behaviour of materials. The Journal focuses on all characterization techniques, including all forms of microscopy (light, electron, acoustic, etc.,) and analysis (especially microanalysis and surface analytical techniques). Developments in both this wide range of techniques and their application to the quantification of the microstructure of materials are essential facets of the Journal. The Journal provides the Materials Scientist/Engineer with up-to-date information on many types of materials with an underlying theme of explaining the behavior of materials using novel approaches. Materials covered by the journal include: Metals & Alloys Ceramics Nanomaterials Biomedical materials Optical materials Composites Natural Materials.