CoxBy合金力学性能、热学性质及电子性质的第一性原理研究
Mechanical,thermal and electronic properties of CoxBy alloys:a first-principles study
金格 1吴尉 1李姗玲 1陈璐 1史俊勤 2贺一轩 2范晓丽2
作者信息
- 1. 西北工业大学 材料学院 先进润滑与密封材料研究中心,西安 710049
- 2. 西北工业大学 材料学院 先进润滑与密封材料研究中心,西安 710049;凝固技术国家重点实验室,西安 710072
- 折叠
摘要
CoxBy合金是一种具有高硬度和高熔点的材料,因其稳定的化学性质、高强度以及良好的热稳定性,在诸多领域具有广泛的应用前景.基于第一性原理方法研究了CoB,Co2B,Co3B,Co23B6,Co5B16 5种CoxBy合金的热力学性质和电子性质.采用能量-应变方法计算了二元合金的弹性常数和相关力学特性,基于准简谐德拜模型计算了有限温度内的德拜温度ΘD和热膨胀系数α等热力学特性.通过对二元合金的力学参数比较,发现CoB合金的综合力学性能在所研究的合金中是最好的;态密度图谱表明5种CoxBy合金均具有较好的金属性和良好的导电性,在电极材料领域有一定的应用潜力,且在Co3B和Co23B6合金中,Co原子的d电子轨道和B原子的p电子轨道间产生了共振峰,说明Co—B间有显著的化学键特征.本研究补充了CoxBy二元合金热力学性能参数的空缺,为Co基或Co—B二元合金材料的设计和应用提供了理论参考.
Abstract
CoxBy alloy with high hardness and high melting point has wide range of applications in many fields because of its stable chemical property,high strength,and good thermal stability.In this work,the thermodynamic and electrical properties of five CoxBy alloys(CoB,Co2B,Co3B,Co23B6 and Co5B16),were studied and compared based on a first-principles approach.The elastic constant and related mechanical property of the binary alloys were calculated by using the energy-strain method,and the thermodynamic properties such as the Debye temperature(ΘD)and the coefficient of thermal expansion(α)within a finite temperature were calculated based on the quasi-simple harmonic Debye model.By comparing the mechanical parameters of the binary alloys,it is found that the comprehensive mechanical property of the CoB alloy is the best among the studied alloys;the state density mapping indicates that all five CoxBy alloys have good metallicity and electrical conductivity,and have some potential applications in the field of electrode materials.In Co3B and Co23B6 alloys,there is a resonance peak between the d electron orbital of Co atom and the p electron orbital of B atom,indicating that there is a significant chemical bond between Co—B.The study complements the gap of thermomechanical property parameters of CoxBy binary alloys and provides a theoretical reference for the design and application of Co based or Co—B binary alloy materials.
关键词
CoxBy合金/热力学性质/电子性质/第一原理计算Key words
CoxBy alloy/thermodynamic property/electronic property/first-principles calculation引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据