Thermodynamic analysis of metal segregation in dual phase high entropy ceramics  

作　　者：Steven M.Smith II William G.Fahrenholtz Gregory E.Hilmas Stefano Curtarolo 

机构地区：[1]Missouri University of Science and Technology,Materials Science and Engineering Department,Rolla,MO,65409,USA [2]Duke University,Department of Mechanical Engineering and Materials Science,Durham,NC,27708,USA [3]Duke University,Center of Autonomous Materials Design,Durham,NC,27708,USA

出　　处：《Journal of Materiomics》2024年第4期889-895,共7页无机材料学学报（英文）

基　　金：Funding for this research was provided by the Office of Naval Research through a Multidisciplinary University Research Initiative(MURI)program under project number N00014-21-1-2515.

摘　　要：Equilibrium Gibbs'free energy calculations were used to determine metal segregation trends between boride and carbide solid solutions containing two metals that are relevant to dual phase high entropy ceramics.The model predicted that Ti had the strongest tendency to segregate to the boride phase followed by Zr,Nb,Mo,V,Hf,and Ta,which matches experimental results of measured compositions.The ratio of a metal in the carbide phase to the content of the same metal in the corresponding metal boride had a linear trend with the change in standard Gibbs'free energy of reaction for a metal carbide reacting with B_(4)C to produce its corresponding metal boride and carbon.The proposed model was used to predict the changes in standard Gibbs'free energy for CrC→CrB_(2) to be−260 kJ and WC→WB_(2) to be 148 kJ,which indicates that Cr has the strongest segregation to the boride and W has the strongest segregation to the carbide.The proposed model can be used to estimate the segregation of metals in dual phase high entropy boride-carbide ceramics of any boride/carbide ratio or metal content.

关 键 词：Dual phase High entropy ceramic BORIDE CARBIDE THERMODYNAMICS 

分 类 号：TQ174.1[化学工程—陶瓷工业]