第一性原理研究掺杂过渡元素对碳化钨性能的影响  

First Principle Study on Tungsten Carbide with Transition Elements

作　　者：王旭飞[1,2] 崔红 刘菊蓉 熊丽红[3] Wang Xufei;Cui Hong;Liu Jurong;Xiong Lihong(School of Mechanical Engineering,Shaanxi University of Technology,Hanzhong 723000,China;Shaanxi Key Laboratory of Industrial Automation,Hanzhong 723000,China;Qinchuan Group Hanjiang Tool Corporation Limited,Hanzhong 723002,China)

机构地区：[1]陕西理工大学机械工程学院,陕西汉中723000 [2]陕西省工业自动化重点实验室,陕西汉中723000 [3]秦川集团汉江工具有限责任公司,陕西汉中723002

出　　处：《稀有金属材料与工程》2021年第3期887-893,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(61701288);陕西省科技计划项目(2020JM-600);陕西省重点实验室项目(18JS020)。

摘　　要：碳化钨(WC)在高温动力装备上应用越来越多,WC的脆性和高密度限制了其更广泛的使用,金属原子掺杂是提高WC性能的一种方法。采用基于第一原理的广义梯度作为近似交换相关函数,研究了A_(0.25)W_(0.75)C(A为Ti、V、Cr、Mn、Co和Ni)的弹性、电子和X射线吸收特性。数值分析结果显示,Ti_(0.25)W_(0.75)C的B/G值(B为体模量,G为剪切模量)为1.869,改性为延性材料,其它均为脆性材料。掺杂25%的V、Co、Ni原子可使WC的脆性降低,掺杂25%的Cr、Mn原子可使WC脆性增大。掺杂后化合物的态密度分布范围减小,费米能级处数值增大,金属性增强,其中Mn_(0.25)W_(0.75)C金属性最强。参杂后X射线吸收谱蓝移,在软X射线波段存在吸收波段,其中Cr、V、Ti在15.74~22.25nm波段出现强吸收峰。研究结果有助于塑性低密度WC类化合物的实验和应用研究。Tungsten carbide(WC)is increasingly used in high-temperature power equipment.The brittleness and high density of WC restrict its wider use.Metal atom doping is a method to improve the performance of WC.The generalized gradient based on the first principle was used as the approximate exchange correlation function.The elastic,electron and X-ray absorption characteristics of A_(0.25)W_(0.75)C(A is Ti,V,Cr,Mn,Co and Ni)were studied.According to the numerical analysis,the BIG value of Ti_(0.25)W_(0.75) c(B is the volume modulus,G is the shear modulus)is 1.869,the material is the modified ductile material,and others are brittle materials.The brittleness of WC decreases with the doping of 25%V,Co and Ni atoms,and brittleness increases with the doping of 25%Cr and Mn atoms After doping,the range of density of state decreases,the value of Fermi level increases,and the metallicity of the compounds increases.Among them,Mn_(0.25)W_(0.75)C has the strongest metallicity.The X-ray absorption spectrum shifts blue after doping,and there is an absorption band in a soft X-ray band.The strong absorption peaks appears in the 15.7422.25 nm band after doping Cr,V,and Ti.The results are helpful to the experimental and application study of WC compounds with plasticity and low density.

关 键 词：碳化钨 掺杂 过渡元素 第一性原理 

分 类 号：TG148[一般工业技术—材料科学与工程] TH142.2[金属学及工艺—金属材料]