{"title":"Effect of heat treatment on microstructure and corrosion behavior of AlCu alloy fabricated by wire arc additive manufacturing","authors":"","doi":"10.1016/j.matchar.2024.114516","DOIUrl":null,"url":null,"abstract":"<div><div>This study investigated the effect of heat treatment on the microstructure and corrosion behavior of the Wire Arc Additive Manufacturing (WAAM) 2319 Al alloy. The results showed that the solid solution treatment and the artificial ageing significantly increased the microhardness of the alloy, and the second phase of the alloy changed from a continuous to a dispersed distribution. Heat treatment led to an increase in pores, and the number of small-size pores increased significantly with the ageing time; this increased the risk of crevice corrosion. The as-deposited WAAM 2319 Al alloy, characterized by an α-Al matrix and coarse intergranular intermetallics Al<sub>2</sub>Cu, underwent galvanic corrosion, which severely damaged the passivation film. The solid solution treatment alleviated this by dissolving the coarse intergranular intermetallics and improving corrosion resistance. During artificial ageing, the corrosion potential decreased gradually as the size and number of precipitated phases increased. Pitting corrosion was the most severe, and corrosion resistance was lowest in the solid solution + peak ageing state.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":null,"pages":null},"PeriodicalIF":4.8000,"publicationDate":"2024-11-02","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/S1044580324008970","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, CHARACTERIZATION & TESTING","Score":null,"Total":0}
引用次数: 0
Abstract
This study investigated the effect of heat treatment on the microstructure and corrosion behavior of the Wire Arc Additive Manufacturing (WAAM) 2319 Al alloy. The results showed that the solid solution treatment and the artificial ageing significantly increased the microhardness of the alloy, and the second phase of the alloy changed from a continuous to a dispersed distribution. Heat treatment led to an increase in pores, and the number of small-size pores increased significantly with the ageing time; this increased the risk of crevice corrosion. The as-deposited WAAM 2319 Al alloy, characterized by an α-Al matrix and coarse intergranular intermetallics Al2Cu, underwent galvanic corrosion, which severely damaged the passivation film. The solid solution treatment alleviated this by dissolving the coarse intergranular intermetallics and improving corrosion resistance. During artificial ageing, the corrosion potential decreased gradually as the size and number of precipitated phases increased. Pitting corrosion was the most severe, and corrosion resistance was lowest in the solid solution + peak ageing state.
本研究探讨了热处理对线弧快速成型(WAAM)2319 Al 合金微观结构和腐蚀行为的影响。结果表明,固溶处理和人工时效显著提高了合金的显微硬度,合金的第二相从连续分布变为分散分布。热处理导致了孔隙的增加,小尺寸孔隙的数量随着时效时间的延长而显著增加;这增加了缝隙腐蚀的风险。沉积后的 WAAM 2319 Al 合金具有α-Al 基体和粗晶粒间金属 Al2Cu 的特点,会发生电化学腐蚀,严重破坏钝化膜。固溶处理通过溶解粗晶间金属间化合物,提高了耐腐蚀性,从而缓解了这一问题。在人工老化过程中,随着析出相尺寸和数量的增加,腐蚀电位逐渐降低。点腐蚀最为严重,固溶+峰值老化状态下的耐腐蚀性能最低。
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.