First Principles Study on Mechanical Properties of Superhard α-Ga Boron  

作　　者：徐源慧 刘会云 郝险峰 陈蓉娜 高发明 

机构地区：[1]Key Laboratory of Applied Chemistry,Yanshan University [2]Department of Computer Technology,Hebei College of Industry and Technology

出　　处：《Chinese Physics Letters》2015年第2期95-98,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant Nos 21303156,21201148,210303156 and 21403185;the Natural Science Foundation of Hebei Province under Grant Nos B2011203121 and B2012203005

摘　　要：The mechanical properties and intrinsic hardness of the α-Ga boron phase （α-Ga-B） are studied by using the combination of first-principles calculations and a semiempirieal macroscopic hardness model. It is found that α- Ga-B is mechanically stable and possesses higher bulk/shear modulus as compared with γ-B28, a newly discovered high-pressure boron phase. The theoretical hardness of α-Ga-B is estimated to be 45 GPa, which is much higher than 38 GPa for γ-B28. The results strongly indicate that α-Ga-B is a potential superhard boron phase. To further obtain insight into the superhard nature of α-Ga-B, we simulate stress-strain curves under tensile and shear deformation. Meanwhile, the microscopic mechanism driving the tensile and shear deformation modes in α-Ga-B is discussed in detail.The mechanical properties and intrinsic hardness of the α-Ga boron phase （α-Ga-B） are studied by using the combination of first-principles calculations and a semiempirieal macroscopic hardness model. It is found that α- Ga-B is mechanically stable and possesses higher bulk/shear modulus as compared with γ-B28, a newly discovered high-pressure boron phase. The theoretical hardness of α-Ga-B is estimated to be 45 GPa, which is much higher than 38 GPa for γ-B28. The results strongly indicate that α-Ga-B is a potential superhard boron phase. To further obtain insight into the superhard nature of α-Ga-B, we simulate stress-strain curves under tensile and shear deformation. Meanwhile, the microscopic mechanism driving the tensile and shear deformation modes in α-Ga-B is discussed in detail.

关 键 词：Ga Boron First Principles Study on Mechanical Properties of Superhard 

分 类 号：TQ163[化学工程—高温制品工业]