Influence of helium-decoration on the interaction between 1/2⟨111⟩ dislocation loop and edge dislocation in BCC iron

被引:16
作者
Zhu, Bida [1 ,2 ]
Huang, Minsheng [1 ,2 ]
Li, Zhenhuan [1 ,2 ]
机构
[1] Huazhong Univ Sci & Technol, Dept Mech, Wuhan 430074, Hubei, Peoples R China
[2] Hubei Key Lab Engn Struct Anal & Safety Assessmen, Luoyu Rd 1037, Wuhan 430074, Hubei, Peoples R China
关键词
Dislocation loop; Irradiation; Helium embrittlement; Molecular dynamics; Monte Carlo; MOLECULAR-DYNAMICS SIMULATIONS; SELF-INTERSTITIAL CLUSTERS; TENSILE PROPERTIES; SCREW DISLOCATION; VACANCY CLUSTERS; ALPHA-IRON; CR; HE; BUBBLES; MICROSTRUCTURE;
D O I
10.1016/j.jnucmat.2019.151866
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
For ferritic steels served as structural materials for future nuclear reactors, a large number of helium atoms are expected to be introduced through transmutation reaction. Current experimental results prove that these helium atoms tend to segregate at different crystal defects and deteriorate the mechanical properties of materials severely. In this work, the helium segregation on 1/2[1 (1) over bar1] dislocation loops (DLs) in body-centered cubic iron and the concomitant hardening effects were investigated by a combination of Monte Carlo and molecular dynamics methods. The Monte Carlo results reveal that the helium atoms are inclined to segregate as helium bubbles at six energetic favorable sites which divide the DLs periphery uniformly, irrespective of the shapes of DLs. The Molecular dynamics simulations were then performed to study the interaction between a moving edge dislocation and the helium-decorated DLs. In order to investigate the helium-decoration effects systematically, influence factors including the DLs size, helium content, and the relative geometric position between edge dislocations and DLs were considered. It is shown that the decoration of helium bubbles suppresses the absorption of DLs by the moving edge dislocation through hindering the movement of dislocation segments during the interaction. Four types of residual products induced by the edge dislocation-DLs interaction are observed, while three of them, including a pure < 100 > DL and two kinds of bi-DLs, had never been reported before. It is also found that helium-segregation overall increases the critical shear stress for the edge dislocation bypassing DLs. These results may be helpful for a deeper atomic-scale comprehens ion of the helium-induced hardening and embrittlement in ferritic steels. (C) 2019 Elsevier B.V. All rights reserved.
引用
收藏
页数:11
相关论文
共 59 条
  • [1] Development of an interatomic potential for phosphorus impurities in α-iron
    Ackland, GJ
    Mendelev, MI
    Srolovitz, DJ
    Han, S
    Barashev, AV
    [J]. JOURNAL OF PHYSICS-CONDENSED MATTER, 2004, 16 (27) : S2629 - S2642
  • [2] [Anonymous], [No title captured]
  • [3] [Anonymous], [No title captured]
  • [4] Observation of the one-dimensional diffusion of nanometer-sized dislocation loops
    Arakawa, K.
    Ono, K.
    Isshiki, M.
    Mimura, K.
    Uchikoshi, M.
    Mori, H.
    [J]. SCIENCE, 2007, 318 (5852) : 956 - 959
  • [5] ACCURATE INTER-MOLECULAR POTENTIAL FOR HELIUM
    AZIZ, RA
    NAIN, VPS
    CARLEY, JS
    TAYLOR, WL
    MCCONVILLE, GT
    [J]. JOURNAL OF CHEMICAL PHYSICS, 1979, 70 (09) : 4330 - 4342
  • [6] AB-INITIO CALCULATIONS FOR HELIUM - A STANDARD FOR TRANSPORT PROPERTY MEASUREMENTS
    AZIZ, RA
    JANZEN, AR
    MOLDOVER, MR
    [J]. PHYSICAL REVIEW LETTERS, 1995, 74 (09) : 1586 - 1589
  • [7] Computer simulation of reactions between an edge dislocation and glissile self-interstitial clusters in iron
    Bacon, D. J.
    Osetsky, Y. N.
    Rong, Z.
    [J]. PHILOSOPHICAL MAGAZINE, 2006, 86 (25-26) : 3921 - 3936
  • [8] On the potentiality of using ferritic/martensitic steels as structural materials for fusion reactors
    Baluc, N
    Schäublin, R
    Spätig, P
    Victoria, M
    [J]. NUCLEAR FUSION, 2004, 44 (01) : 56 - 61
  • [9] Atomistic study of the hardening of ferritic iron by Ni-Cr decorated dislocation loops
    Bonny, G.
    Bakaev, A.
    Terentyev, D.
    Zhurkin, E.
    Posselt, M.
    [J]. JOURNAL OF NUCLEAR MATERIALS, 2018, 498 : 430 - 437
  • [10] Assessment of hardening due to dislocation loops in bcc iron: Overview and analysis of atomistic simulations for edge dislocations
    Bonny, G.
    Terentyev, D.
    Elena, J.
    Zinovev, A.
    Minov, B.
    Zhurkin, E. E.
    [J]. JOURNAL OF NUCLEAR MATERIALS, 2016, 473 : 283 - 289