中国物理B ›› 2019, Vol. 28 ›› Issue (11): 116106-116106.doi: 10.1088/1674-1056/ab4bb9

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

First-principles studies on carbon diffusion in tungsten

Chi Song(宋驰), Xiang-Shan Kong(孔祥山), C S Liu(刘长松)   

  1. 1 College of Science, Jinling Institute of Technology, Nanjing 211169, China;
    2 Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China
  • 收稿日期:2019-06-19 修回日期:2019-09-28 出版日期:2019-11-05 发布日期:2019-11-05
  • 通讯作者: Xiang-Shan Kong E-mail:xskong@issp.ac.cn
  • 基金资助:
    Project supported by the National Key Research and Development Program of China (Grant No. 2018YFE0308102), the National Natural Science Foundation of China (Grant Nos. 11735015 and 51771185), the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (Grant No. 17KJB140008), and Jinling Institute of Technology, China (Grant Nos. jit-fhxm-201601 and jit-b-201616).

First-principles studies on carbon diffusion in tungsten

Chi Song(宋驰)1, Xiang-Shan Kong(孔祥山)2, C S Liu(刘长松)2   

  1. 1 College of Science, Jinling Institute of Technology, Nanjing 211169, China;
    2 Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China
  • Received:2019-06-19 Revised:2019-09-28 Online:2019-11-05 Published:2019-11-05
  • Contact: Xiang-Shan Kong E-mail:xskong@issp.ac.cn
  • Supported by:
    Project supported by the National Key Research and Development Program of China (Grant No. 2018YFE0308102), the National Natural Science Foundation of China (Grant Nos. 11735015 and 51771185), the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (Grant No. 17KJB140008), and Jinling Institute of Technology, China (Grant Nos. jit-fhxm-201601 and jit-b-201616).

摘要: The carbon diffusivity in tungsten is one fundamental and essential factor in the application of tungsten as plasma-facing materials for fusion reactors and substrates for diamond growth. However, data on this are quite scarce and largely scattered. We perform a series of first-principles calculations to predict the diffusion parameters of carbon in tungsten, and evaluate the effect of temperature on them by introducing lattice expansion and phonon vibration. The carbon atom prefers to occupy octahedral interstitial site rather than tetrahedral interstitial site, and the minimum energy path for its diffusion goes through a tetrahedral site. The temperature has little effect on the pre-exponential factor but a marked effect on the activation energy, which linearly increases with the temperature. Our predicted results are well consistent with the experimental data obtained at high temperature (>1800 K) but significantly larger than the experimental results at low temperature (<1800 K).

关键词: metals and alloys, diffusion, computer simulations

Abstract: The carbon diffusivity in tungsten is one fundamental and essential factor in the application of tungsten as plasma-facing materials for fusion reactors and substrates for diamond growth. However, data on this are quite scarce and largely scattered. We perform a series of first-principles calculations to predict the diffusion parameters of carbon in tungsten, and evaluate the effect of temperature on them by introducing lattice expansion and phonon vibration. The carbon atom prefers to occupy octahedral interstitial site rather than tetrahedral interstitial site, and the minimum energy path for its diffusion goes through a tetrahedral site. The temperature has little effect on the pre-exponential factor but a marked effect on the activation energy, which linearly increases with the temperature. Our predicted results are well consistent with the experimental data obtained at high temperature (>1800 K) but significantly larger than the experimental results at low temperature (<1800 K).

Key words: metals and alloys, diffusion, computer simulations

中图分类号:  (Physical radiation effects, radiation damage)

  • 61.80.-x
61.82.Bg (Metals and alloys)