%0 Journal Article %T 利用第一性原理计算方法对NbMoTaWVx 高熵合金的研究<br>Studies on NbMoTaWVx High??Entropy Alloys Based on Ab Initio Theory Calculation Method %A 丁欣恺 %A 孙琨 %A 张猛 %A 方亮 %A 邢建东 %J 西安交通大学学报 %D 2018 %R 10.7652/xjtuxb201811013 %X 为了分析NbMoTaWVx高熵合金中V组元对材料特性的影响,利用第一性原理计算方法对其进行了研究,该方法是一种基于密度泛函理论框架下的精确糕模势轨道结合相干势近似模型的方法。首先,对NbMoTaWVx高熵合金的相与结构性质进行了研究,结果表明:当0≤x≤1??5时,NbMoTaWVx高熵合金在平衡态中的最稳定构型为体心立方结构;V组元物质的量比的增加会减小NbMoTaWVx高熵合金的密度、晶格尺寸和体心立方相的稳定性。其次,计算了NbMoTaWVx高熵合金的弹性力学性质,结果表明:随着V组元物质的量比的增加,合金的内在塑性会提高,理论强度会降低,弹性各向异性几乎不变。<br>To analyze the effect of V element in NbMoTaWVx high??entropy alloys (HEAs), an ab initio theory calculation method is utilized. Exact muffin??tin orbitals which bases on density functional theory and the model with the coherent potential approximation of the close??packed ideal crystal structure are combined together to form the method. Firstly, the phase and the structure of NbMoTaWVx HEAs are investigated. Results show that the most thermodynamically stable phases of NbMoTaWVx HEAs in the equilibrium state is body??centered cubic (bcc) phase when 0≤x≤1??5. And the increasing ratio of amount of substance of V element decreases mass density, lattice size and bcc phase stability of NbMoTaWVx HEAs. Then elastic properties of these HEAs are also calculated, and results show that the theoretical plasticity of alloys becomes better and the theoretical strength decreases with increasing molar fraction of V element, but it has no effect on the anisotropy of NbMoTaWVx HEAs %K NbMoTaWVx %K 高熵合金 %K 结构 %K 性质< %K br> %K NbMoTaWVx %K high entropy alloys %K structure %K property %U http://zkxb.xjtu.edu.cn/oa/DArticle.aspx?type=view&id=201811013