{"title":"Flash sintering of high-purity alumina at room temperature","authors":"Yueji Li, Qingguo Chi, Ziyang Yan, Nianping Yan, Jinling Liu, Rongxia Huang, Xilin Wang","doi":"10.26599/jac.2023.9220816","DOIUrl":null,"url":null,"abstract":"For the first time, the flash sintering (FS) of high-purity alumina at room temperature, which was previously considered unachievable due to its low electrical conductivity, was conducted herein. The electrical arc originating from surface flashover was harnessed to induce FS at room temperature and low air pressure. The successful FS of high-purity alumina was realized at 60 kPa under the arc constraint, resulting in a notable relative density of the alumina sample of 98.7%. The electric–thermal coupling between the arc and high-purity alumina sample during the arc-induced FS process was analyzed via the finite element simulation method. The results revealed the thermal and electrical effects of the arc on the sample, which ultimately enhance the electrical conductivity of the alumina sample. The formation of a conductive channel on the sample surface, a result of increased electrical conductivity, was the pivotal factor in achieving FS in high-purity alumina at room temperature. The arc constraint technique can be applied to numerous materials, such as ionic conductors, semiconductors, and even insulators, under room-temperature and low-air-pressure conditions.","PeriodicalId":14862,"journal":{"name":"Journal of Advanced Ceramics","volume":null,"pages":null},"PeriodicalIF":18.6000,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Advanced Ceramics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.26599/jac.2023.9220816","RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, CERAMICS","Score":null,"Total":0}
引用次数: 0
Abstract
For the first time, the flash sintering (FS) of high-purity alumina at room temperature, which was previously considered unachievable due to its low electrical conductivity, was conducted herein. The electrical arc originating from surface flashover was harnessed to induce FS at room temperature and low air pressure. The successful FS of high-purity alumina was realized at 60 kPa under the arc constraint, resulting in a notable relative density of the alumina sample of 98.7%. The electric–thermal coupling between the arc and high-purity alumina sample during the arc-induced FS process was analyzed via the finite element simulation method. The results revealed the thermal and electrical effects of the arc on the sample, which ultimately enhance the electrical conductivity of the alumina sample. The formation of a conductive channel on the sample surface, a result of increased electrical conductivity, was the pivotal factor in achieving FS in high-purity alumina at room temperature. The arc constraint technique can be applied to numerous materials, such as ionic conductors, semiconductors, and even insulators, under room-temperature and low-air-pressure conditions.
期刊介绍:
Journal of Advanced Ceramics is a single-blind peer-reviewed, open access international journal published on behalf of the State Key Laboratory of New Ceramics and Fine Processing (Tsinghua University, China) and the Advanced Ceramics Division of the Chinese Ceramic Society.
Journal of Advanced Ceramics provides a forum for publishing original research papers, rapid communications, and commissioned reviews relating to advanced ceramic materials in the forms of particulates, dense or porous bodies, thin/thick films or coatings and laminated, graded and composite structures.