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This article used molecular dynamics to simulate the surface binding energy of W1-xVx ( x = 0, 0.0625, 0.125, 0.25, 0.3125, 0.5) alloys along the (100) direction, considering the volume effect. The results showed that forming an alloy between W and V significantly improved the surface binding energy of W within the simulated proportion range, and the surface binding energy of W increased with increasing V proportion. However, when the simulated surface binding energy was input into the Monte Carlo program (SRIM-2013) to calculate the sputtering yield of W-V alloys, it was found that the alloy with V only greatly reduced the sputtering yield of W in the alloy, and the total sputtering yield of the alloy was higher than that of pure tungsten. Therefore, W still had the best anti-sputtering ability in the simulated material. The obtained results provided a reference for the selection of plasma-facing materials in future nuclear fusion. Introduction Developing efficient and clean new energy sources is necessary in any era, and nuclear fusion is currently the most promising new energy source that can lead humanity into the next era. However, realizing nuclear fusion still faces many challenges, including finding materials that can long-term accommodate fusion plasma without polluting it [1], [2], [3]. Tungsten (W) has many advantages that make it the most promising material for plasma-facing materials (PFMs), such as high melting point, good thermal conductivity, strong splashing resistance, and low tritium retention rate [4], [5], [6], [7], [8]. However, using W in PFMs also requires solving some problems, such as easy oxidation, low ductility at room temperature, high ductile-to-brittle transition temperature (DBTT), and difficulty in processing [9], [10], [11], [12]. Fortunately, through continuous research, alloying had been discovered to not only improve the performance of materials in various aspects but also may exhibit unexpected excellent properties. Therefore, alloying had become one of the best choices to solve this problem. The fact tells us that forming an alloy with other elements could indeed change some of the drawbacks of W. For example, forming an alloy with V can improve the material's resistance to irradiation, improve mechanical properties, and have stronger phase stability [13], [14], [15], [16]. In addition, the thermodynamic properties of W-V alloys could be adjusted through alloy design to make them more suitable for different environments and requirements [17]. These advantages make W-V alloys a promising material for use in nuclear fusion reactors and other nuclear energy applications in high-radiation environments. Despite the many advantages of W-V alloys, there had been little detailed research on the impact of alloying on the materials' sputtering resistance. Sputtering of materials has always been one of the important reasons for contamination and experimental interference, so it is necessary to minimize the impact of sputtering on fusion parameters by maximizing the materials' sputtering resistance [18]. In nuclear fusion, the production of helium ash is inevitable, and so far, there is no effective method to deal with it, which leads to its unavoidable impact on the radiation damage of plasma-facing materials. The energy of helium ions ranges from 10 eV to several keV [2,[19], [20], [21]]. Therefore, in this paper, molecular dynamics simulations were used to study the impact of helium on the sputtering resistance of W-V alloys. The obtained results provide reference for the study of plasma-facing materials. Section snippets Surface binding energy The typical definition of surface energy is: E S B E = E a t o m + E S + V − E S Here, E S refers to the total energy of a crystal with a complete surface, E S + V refers to the total energy of a crystal with a single vacancy surface, and both surfaces, with or without vacancies, were relaxed. E atom refers to the internal energy of the removed atom. The total energy of a general crystal refers to the sum of the interatomic potential energy and the internal energy of all atoms. However, surface binding energy refers ESBE As shown in Fig. 2, the surface binding energies of each non-equivalent vacancy atom in W-V alloy are plotted for six different crystal models, with each curve fitted using Eq. (3). y = y 0 + A 1 e − x / t 1 + A 2 e − x / t 2 It could be observed that the surface binding energy of V atoms is mainly within the range of 6.2–6.9 eV, while that of W atoms was within the range of 9.4–10.3 eV. As the crystal model increases in size, the surface binding energy gradually tends to a stable value, which is since the actual Summary and conclusions This study used the molecular dynamics software LAMMPS to simulate the surface binding energy of W1-xVx ( x = 0, 0.0625, 0.125, 0.25, 0.3125, 0.5) alloys along the (100) direction, taking into account the influence of volume effects on surface binding energy. The obtained simulation results were used as input for the Monte Carlo software SRIM-2013 to calculate the sputtering yield caused by helium ion incidence at different energies and angles, and to analyze the material's resistance to CRediT authorship contribution statement Xiaolong Li: Methodology, Software, Validation, Formal analysis, Data curation, Writing – original draft, Visualization. Xin Zhang: Conceptualization, Writing – review & editing, Supervision, Project administration, Funding acquisition. Yuhong Xu: Supervision, Funding acquisition. Guangjiu Lei: Supervision. Sanqiu Liu: Supervision, Funding acquisition. Heng Li: Writing – review & editing. Zilin Cui: Investigation, Resources, Writing – review & editing. Yiqin Zhu: Writing – review & editing. Jun Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgments This work was supported by the Natural Science Foundation of Sichuan Province (Grant No. 2022NSFSC0331 ), Sichuan International Science and Technology Innovation Cooperation Project ( 2021YFH0066 ), National Key R&D Program of China ( 2022YFE03070000 , 2022YFE03070002 ). References (35) R.A. Pitts et al. A full tungsten divertor for ITER: physics issues and design status J. Nucl. Mater. (2013) H. Iwakiri et al. Microstructure evolution in tungsten during low-energy helium ion irradiation J. Nucl. Mater. (2000) N. Yoshida et al. 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