Unveiling structural features and mechanical properties of amorphous Si_(2)BC_(3)N by density functional theory  

作　　者：Yuchen Liu Yu Zhou Dechang Jia Zhihua Yang Daxin Li Bin Liu 

机构地区：[1]Institute for Advanced Ceramics,School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150080,China [2]School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China [3]Zhejiang Laboratory,Hangzhou 311100,China

出　　处：《Journal of Materials Science & Technology》2023年第8期103-112,共10页材料科学技术（英文版）

基　　金：This work was financially supported by the National Natu-ral Science Foundation of China(Nos.52002092,51832002,and 52172071);the Program for Professor of Special Appointment(East-ern Scholar)at Shanghai Institutions of Higher Learning(No.GZ2020012);Key Research Project of Zhejiang Laboratory(No.2021PE0AC02);Heilong Jiang Natural Science Fund for Young Scholars(No.YQ2021E017)。

摘　　要：The atomic structural features and the mechanical properties of the Si_(2)BC_(3)N are investigated employ-ing ab-initio calculations.The chemical bonding types and their proportion are clarified.The tetrahedral and trigonal configurations,together with their nesting,are identified,which contribute to the flexibil-ity of structural characteristics.The Si-related coordination aggravates the inhomogeneous distribution of chemical bonding and weakens the tetrahedral units.The accompanying polyhedral distortion is quanti-tatively reflected by the bond length and its deviation of polyhedron units.The elastic moduli and the ideal strengths of Si_(2)BC_(3)N are found to be lower than SiC and Si_(3)N_(4),as a result of the weakening effect of coordination Si on tetrahedral units and the existence of easily distorted trigona.The balance between tetrahedral and trigonal features through composition tailor is believed an effective way for the design of Si-B-C-N ceramics for structural applications.

关 键 词：Amorphous SiBCN Ab-initio calculations Atomic structure Electronic structure Mechanical properties 

分 类 号：TB30[一般工业技术—材料科学与工程] TN15[电子电信—物理电子学]