T. Mitamura, E.L. Hall, W.D. Kingery, J.B. Vander Sande
{"title":"Grain boundary segregation of iron in polycrystalline magnesium oxide observed by STEM","authors":"T. Mitamura, E.L. Hall, W.D. Kingery, J.B. Vander Sande","doi":"10.1016/0390-5519(79)90020-6","DOIUrl":null,"url":null,"abstract":"<div><p>Utilizing X-ray microanalysis in samples studied with scanning transmission electron microscopy, substantial grain boundary segregation of Fe is found in grain boundaries in polycrystalline MgO. Samples studied contained between 540 and 5400 cation ppm Fe. Grain boundary segregation in the region within 200 Å of the boundary was found in all cases, with the amount of segregation increasing with increasing Fe content. Samples slow-cooled from 1500°C showed an increased amount of segregation attributed to continued diffusion during cooling. Samples quenched from 1100°C showed greater segregation than those quenched from 1500°C, consistent with space charge theory. In some samples precipitates were observed which are correlated with a low-temperature phase diagram for the solidus in the iron oxide-magnesium oxide system. In addition to Fe, grain boundary segregation of Ca and Si impurities in the samples was also observed.</p></div>","PeriodicalId":100227,"journal":{"name":"Ceramurgia International","volume":"5 4","pages":"Pages 131-136"},"PeriodicalIF":0.0000,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0390-5519(79)90020-6","citationCount":"19","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ceramurgia International","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0390551979900206","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 19
Abstract
Utilizing X-ray microanalysis in samples studied with scanning transmission electron microscopy, substantial grain boundary segregation of Fe is found in grain boundaries in polycrystalline MgO. Samples studied contained between 540 and 5400 cation ppm Fe. Grain boundary segregation in the region within 200 Å of the boundary was found in all cases, with the amount of segregation increasing with increasing Fe content. Samples slow-cooled from 1500°C showed an increased amount of segregation attributed to continued diffusion during cooling. Samples quenched from 1100°C showed greater segregation than those quenched from 1500°C, consistent with space charge theory. In some samples precipitates were observed which are correlated with a low-temperature phase diagram for the solidus in the iron oxide-magnesium oxide system. In addition to Fe, grain boundary segregation of Ca and Si impurities in the samples was also observed.