【摘要】 基于密度泛函理论，研究了不同结构对无序Al_1-xLi_x（x=0.25,0.5和0.75）的弹性模量、各向异性和理想抗拉强度的影响。结果表明，Al_1-xLi_x相可以在0 K时形成稳定结构，但Al_0.75Li_0.25相的形成难度较大。对于相同成分的Al_1-xLi_x相，BCC结构具有相对较弱的抗体积变形能力。当Li含量（摩尔分数）从5%提高到75%,FCC Al_1-xLi_x相发生韧脆性转变，可能是由金属键转变为共价键导致。BCC Al_0.75Li_0.25的弹性性质展现出显著的各向异性，而FCC Al_0.75Li_0.25和BCC Al_0.25Li_0.75趋于各向同性。相同结构的Al_1-xLi_x相的理想抗拉强度随Li含量的增加而呈降低趋势。更多还原

【Abstract】 Effects of different structures on the elastic modulus, anisotropy and ideal tensile strength of disordered Al_1-xLi_x（x=0.25,0.5 and 0.75） were investigated based on density functional theory. The results indicate that the Al_1-xLi_x phase leads to a stable structure at 0 K, while the formation of Al_0.75Li_0.25 phase is difficult. For the Al_1-xLi_x phase with constant composition, BCC structure exhibits a relatively weak resistance to volume deformation. With molar fraction of Li increasing from 50% to 75%, FCC Al_1-xLi_x phase undergoes a ductile-brittle transition, which is attributed to the transformation from metallic bonds to directional covalent bonds. The elastic properties of BCC Al_0.75Li_0.25 exhibit significant anisotropy, while FCC Al_0.75Li_0.25 and BCC Al_0.75Li_0.25 tend to be isotropic. With the increase of Li content, the ideal tensile strength of Al_1-xLi_x phases with the same structure is decreased.更多还原