Burrage Kaleb, Lin Chia-Min, Chen Cheng-Chien, Vohra Yogesh K
Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
Department of Physics, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
Materials (Basel). 2022 Apr 9;15(8):2762. doi: 10.3390/ma15082762.
The compression behavior of the hexagonal AlB phase of Hafnium Diboride (HfB) was studied in a diamond anvil cell to a pressure of 208 GPa by axial X-ray diffraction employing platinum as an internal pressure standard. The deformation behavior of HfB was studied by radial X-ray diffraction technique to 50 GPa, which allows for measurement of maximum differential stress or compressive yield strength at high pressures. The hydrostatic compression curve deduced from radial X-ray diffraction measurements yielded an ambient-pressure volume V = 29.73 Å3/atom and a bulk modulus K = 282 GPa. Density functional theory calculations showed ambient-pressure volume V = 29.84 Å3/atom and bulk modulus K = 262 GPa, which are in good agreement with the hydrostatic experimental values. The measured compressive yield strength approaches 3% of the shear modulus at a pressure of 50 GPa. The theoretical strain-stress calculation shows a maximum shear stress τ~39 GPa along the (1-10) [110] direction of the hexagonal lattice of HfB, which thereby can be an incompressible high strength material for extreme-environment applications.
在金刚石对顶砧中，以铂作为内压标准，通过轴向X射线衍射研究了二硼化铪（HfB）六方AlB相在208吉帕压力下的压缩行为。通过径向X射线衍射技术研究了HfB在50吉帕压力下的变形行为，该技术可用于测量高压下的最大微分应力或压缩屈服强度。由径向X射线衍射测量得出的静水压缩曲线给出了常压下的体积V = 29.73 ų/原子和体模量K = 282吉帕。密度泛函理论计算表明常压下的体积V = 29.84 ų/原子和体模量K = 262吉帕，这与静水实验值吻合良好。在50吉帕压力下，测得的压缩屈服强度接近剪切模量的3%。理论应变-应力计算表明，沿HfB六方晶格的(1-10)[110]方向的最大剪应力τ~39吉帕，因此HfB可成为用于极端环境应用的不可压缩高强度材料。
