{"title":"Defending against fluorine corrosion: Insights from FeCoNiCrMo high-entropy alloy behavior in hydrofluoric acid solutions","authors":"","doi":"10.1016/j.jmrt.2024.09.097","DOIUrl":null,"url":null,"abstract":"<div><p>The surging demand for advanced fluorine corrosion-resistant materials underscores their significance in ensuring operational safety and reliability across various industries. This study investigates the corrosion behavior of the FeCoNiCrMo high-entropy alloy (HEA) <em>via</em> a series of 28-day immersion tests in hydrofluoric acid (HF) solutions. The results demonstrate the FeCoNiCrMo HEA's superior corrosion-resistant performance in HF environments, exhibiting remarkably low corrosion rates of 0.179 mm/y, 0.276 mm/y, and 0.352 mm/y in 20 vol%, 30 vol%, and 40 vol% HF solutions, respectively. Comprehensive phase and microstructural characterizations were conducted on samples exposed to the 40 vol% HF solution to elucidate the corrosion mechanisms. The study revealed that localized pitting corrosion preferentially initiates within the interdendritic regions of the HEA matrix upon HF exposure. During the intermediate stage, micro-galvanic corrosion occurs between the dendritic arms and interdendritic regions, leading to the formation of a uniform and compact corrosion product film on the alloy surface. This film, enriched with Mo, Cr, and O, provides temporary protection. However, as corrosion progresses, the partial detachment of particulate corrosion products compromises the integrity of the film, resulting in increased dissolution within the interdendritic regions and the formation of irregular corrosion grooves in the later stage. These insights significantly enhance the understanding of the corrosion mechanisms of FeCoNiCrMo HEA in HF environments and provide valuable guidance for developing innovative protective materials designed for fluorine-rich engineering applications.</p></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":null,"pages":null},"PeriodicalIF":6.2000,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2238785424021021/pdfft?md5=380da516d67dfad02061f999e8907890&pid=1-s2.0-S2238785424021021-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Materials Research and Technology-Jmr&t","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2238785424021021","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
The surging demand for advanced fluorine corrosion-resistant materials underscores their significance in ensuring operational safety and reliability across various industries. This study investigates the corrosion behavior of the FeCoNiCrMo high-entropy alloy (HEA) via a series of 28-day immersion tests in hydrofluoric acid (HF) solutions. The results demonstrate the FeCoNiCrMo HEA's superior corrosion-resistant performance in HF environments, exhibiting remarkably low corrosion rates of 0.179 mm/y, 0.276 mm/y, and 0.352 mm/y in 20 vol%, 30 vol%, and 40 vol% HF solutions, respectively. Comprehensive phase and microstructural characterizations were conducted on samples exposed to the 40 vol% HF solution to elucidate the corrosion mechanisms. The study revealed that localized pitting corrosion preferentially initiates within the interdendritic regions of the HEA matrix upon HF exposure. During the intermediate stage, micro-galvanic corrosion occurs between the dendritic arms and interdendritic regions, leading to the formation of a uniform and compact corrosion product film on the alloy surface. This film, enriched with Mo, Cr, and O, provides temporary protection. However, as corrosion progresses, the partial detachment of particulate corrosion products compromises the integrity of the film, resulting in increased dissolution within the interdendritic regions and the formation of irregular corrosion grooves in the later stage. These insights significantly enhance the understanding of the corrosion mechanisms of FeCoNiCrMo HEA in HF environments and provide valuable guidance for developing innovative protective materials designed for fluorine-rich engineering applications.
期刊介绍:
The Journal of Materials Research and Technology is a publication of ABM - Brazilian Metallurgical, Materials and Mining Association - and publishes four issues per year also with a free version online (www.jmrt.com.br). The journal provides an international medium for the publication of theoretical and experimental studies related to Metallurgy, Materials and Minerals research and technology. Appropriate submissions to the Journal of Materials Research and Technology should include scientific and/or engineering factors which affect processes and products in the Metallurgy, Materials and Mining areas.