{"title":"Effect of Deuterium Loading on Permeation of Deuterium Through Niobium at Relative Low Pressure","authors":"Qi Dan, Ru Tang, Xiaohong Chen","doi":"10.1007/s10894-024-00448-1","DOIUrl":null,"url":null,"abstract":"<div><p>In the temperature range of (823–1023) K, we investigated the permeation behavior of deuterium in niobium under a pressure of (1–20) kPa and observed gradual changes in permeability and diffusivity during the permeation cycles. Notably, as the permeation cycles increased, the permeability curve exhibited an abnormal-to-normal transformation phenomenon. Increasing deuterium pressure at this stage could restore the permeability to its abnormal state. By comparing the permeation cycles of niobium foils with different oxidation degrees at 1023 K, we found that surface oxide thickness did not affect the abnormal phenomenon but reduced the diffusion coefficient of deuterium during initial permeation. Additionally, we observed that the permeation flux was proportional to the square root of pressure, indicating that diffusion still controlled permeation. After the deuterium loading, the abnormal phenomenon of the 1st permeation disappeared, and the diffusivity of deuterium in niobium decreased. The results suggested that the abnormal phenomena in 1st permeation were primarily caused by the irreversible defects resulting from the interaction between niobium and deuterium in the bulk phase and were not related to the surface effect. The pressure, concentration, and temperature of deuterium in the bulk phase accelerated the interaction between niobium and deuterium and promoted the transition of deuterium in niobium to abnormal permeation. These research findings hold significant implications for the application of niobium as a hydrogen isotope separation and purification material.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"43 2","pages":""},"PeriodicalIF":1.9000,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Fusion Energy","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s10894-024-00448-1","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"NUCLEAR SCIENCE & TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
In the temperature range of (823–1023) K, we investigated the permeation behavior of deuterium in niobium under a pressure of (1–20) kPa and observed gradual changes in permeability and diffusivity during the permeation cycles. Notably, as the permeation cycles increased, the permeability curve exhibited an abnormal-to-normal transformation phenomenon. Increasing deuterium pressure at this stage could restore the permeability to its abnormal state. By comparing the permeation cycles of niobium foils with different oxidation degrees at 1023 K, we found that surface oxide thickness did not affect the abnormal phenomenon but reduced the diffusion coefficient of deuterium during initial permeation. Additionally, we observed that the permeation flux was proportional to the square root of pressure, indicating that diffusion still controlled permeation. After the deuterium loading, the abnormal phenomenon of the 1st permeation disappeared, and the diffusivity of deuterium in niobium decreased. The results suggested that the abnormal phenomena in 1st permeation were primarily caused by the irreversible defects resulting from the interaction between niobium and deuterium in the bulk phase and were not related to the surface effect. The pressure, concentration, and temperature of deuterium in the bulk phase accelerated the interaction between niobium and deuterium and promoted the transition of deuterium in niobium to abnormal permeation. These research findings hold significant implications for the application of niobium as a hydrogen isotope separation and purification material.
期刊介绍:
The Journal of Fusion Energy features original research contributions and review papers examining and the development and enhancing the knowledge base of thermonuclear fusion as a potential power source. It is designed to serve as a journal of record for the publication of original research results in fundamental and applied physics, applied science and technological development. The journal publishes qualified papers based on peer reviews.
This journal also provides a forum for discussing broader policies and strategies that have played, and will continue to play, a crucial role in fusion programs. In keeping with this theme, readers will find articles covering an array of important matters concerning strategy and program direction.