Studying The Stability And Potential Of The Impurity Atoms Embedded In TiV Alloy Using First-principles

As a New Energy,nuclear energy is expected to solve the future energy crisis.The vanadium alloy has become identified as a leading candidate materials for first-wall of the fusion reactor.However,The impurity atoms are inevitably doped before the use of vanadium alloys.For example,in the preparation or service of the alloy,the doping of the impurity atoms such as H He C O will inevitably enter into the vanadium alloy at any time,which will have an important effect on the physical properties of the vanadium alloy.The stability and potential function of impurity atoms embedded in vanadium alloy can provide the guidance for the analysis and design of the material,which has important theoretical and practical significance.In this paper,based on density-functional theory,The binding energy and lattice distortion of four impurity atoms(H/He/C/O)embedded in the interstitial site of vanadium and titanium vanadium alloys are calculated,and the stability of impurity atoms in V and TiV alloys is researched by using First-principles;Based on the four kinds of nonmetallic atoms(H/He/C/O)and two metal atoms(Ti/V)as the research object,This paper fits the Lennard-Jones potential between the metal and non-metal atoms and the 2NN MEAM potential of the FCC TiV alloy.The study shows that:(1)H and He atoms are more likely to occupy the tetrahedral interstitial site in the vanadium,while the C and O atoms are more stable in the octahedral interstitial site;(2)As for BCC TiV alloy,the four impurity atoms are more stable in the tetrahedral interstitial site;(3)The L-J potential of the fitting V-C is in good agreement with previous literature,and the other groups of metal and nonmetallic elements in the fitting is consistent with the basic curve of L-J;(4)Based on Ti and V potential parameters of single atoms,the potential parameters of the FCC configuration TiV alloy are verified by First-principles and the results are more reliable.The potential parameters obtained in this article are applicable to the FCC structure and also applicable to any phase structure in the phase diagram.