SEMINAR

The State Key Lab of High Performance Ceramics and Superfine Microstructure

Structural Ceramics Engineering Research Center

中国科学院上海硅酸盐研究所

Simulation of mechanical properties of AlMgB₁₄-based compounds

Speaker：Prof. Oleksiy Bystrenko 

Institute for Problems in Materials Science, National Academy of Sciences of Ukraine 

时间：12月23日（周一）上午9:00

地点：长宁园区2号楼521会议室 

联系人：张景贤研究员，刘建军研究员　  

　　Lecture：Simulation of mechanical properties of AlMgB₁₄-based compounds 

　　First principle simulations of bulk moduli for a number of XYB14-compounds (X=Al,V,Nb,Ti,Ta; Y=Mg,N,C,Si,Sc,Ti,V,Cr,Y,Zr,Nb,W,Ta) were performed in order to determine the compositions with potentially better hardness. The calculations were carried out on the basis of stress-strain approach within the framework of density functional theory with the use of ultrasoft pseudopotentials and generalized gradient approximation of exchange-correlation energy. The results of simulations indicate that the moderate increase in bulk moduli is observed for the case of replacement of Mg-atom by transitional metals of III-V groups with partially occupied d-shell. Comparative study of electronic structure of AlMgB14 and AlTaB14 has revealed in this case significant contribution of d-electrons to density of states of valence band. The ways of accurate simulation of indentation process and hardness for  multigrain composite materials on the basis of phase field models are discussed.