Initial investigation of B4C-TiB2 composites as neutron absorption material for nuclear reactors

JOURNAL OF NUCLEAR MATERIALS

卷:539

Article

Wang, Ji¹  Ren, Donglou²  Chen, LeiLei³  Man, Guian⁴  Zhang, Houyuan⁴  Zhang, Hongpeng⁵  Luo, Laihui¹  Li, Weiping¹  Pan, Yanbo¹  Gao, Peifeng⁴  Zhu, Yabin⁵  Wang, Zhiguang⁵ 

[1] Ningbo Univ, Sch Phys Sci & Technol, Ningbo 315211, Peoples R China

[2] Univ Rennes, ISCR Inst Sci Chim Rennes, CNRS, UMR 6226, F-35000 Rennes, France

[3] Chinese Acad Sci, Ningbo Inst Mat Technol & Engn, Ningbo 315201, Peoples R China

[4] Lanzhou Univ, Coll Civil Engn & Mech, Key Lab Mech Western Disaster & Environm, Minist Educ, Lanzhou 730000, Peoples R China

[5] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China

关键词: Neutron absorber;    B4C pellet;    He irradiation;    Crack propagation;    Finite element;   

DOI  :  10.1016/j.jnucmat.2020.152275

来源: Elsevier

【 摘 要 】

In this study, a specifically designed B4C-TiB2 composite with the typical microstructural feature of a TiB2 network (cages) that encapsulates a B4C matrix was fabricated by the molten-salt and spark plasma sintering (SPS) method. The finite-element (FE) calculation results show that the connected TiB2 cages constitute a thermally conductive network, which effectively improves the overall thermal conductivity of the composite; these results agree well with the experimental results. Moreover, the Vickers indentation results reveal that the TiB2 network (cages) can effectively impinge/block the propagation of cracks, which increases the composite toughness. The composite was subjected to helium (He) ion irradiation to simulate the situation in which the B4C-TiB2 composites serve as neutron absorption material, and for which case a high quantity of He atoms is produced by the B-10(n, alpha)Li-7 nuclear reaction. According to the transmission electron microscopy (TEM) results, the interfaces between TiB2 and B4C act as effective sinks for He atoms, and are preferential nucleation sites for He bubbles. The theoretical and experimental results show that when the B4C-TiB2 composites serve as neutron absorption pellets in nuclear reactors, they exhibit a better resistance to their disintegration than pure B4C pellets. Consequently, the performance of the control rods of nuclear reactors can be improved. (C) 2020 Elsevier B.V. All rights reserved.

【 授权许可】

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