铸态U-10wt%Zr合金的微观组织及第二相

doi:10.13251/j.issn.0254-6051.2025.06.012

摘要/Abstract

摘要： 结合金相(OM)、扫描电镜(SEM)、能谱分析(EDS)等手段,对真空感应熔炼浇铸的U-10wt%Zr合金基体微观组织及第二相进行了表征分析和评价。结果表明:铸态U-10wt%Zr合金显微组织主要由微米级针状或带状区域构成;高倍SEM下铸态U-10wt%Zr合金的基体组织呈现出两相交替分布的片层状结构,相邻片层平行分布,两相分别为α-U相和δ-UZr₂相;铸态U-10wt%Zr合金中第二相形貌呈现近似椭圆形,在基体中分布不均匀,其成分为Zr析出相。研究结果对进一步认识U-Zr合金初始微观组织状态及与辐照行为关联性具有重要意义。

关键词: U-Zr合金, 微观组织, 相组成, 第二相

Abstract: Microstructure and second phases of U-10wt%Zr alloy matrix cast by vacuum induction melting were characterized, analyzed, and evaluated by combining metallographic (OM), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS). The research results indicate that the metallographic structure of the as-cast U-10wt%Zr alloy is mainly composed of micro scale needle like or strip like regions. Under high magnification SEM, the matrix structure of the as-cast U-10wt%Zr alloy exhibits lamellar structures with alternating distributions of two phases, with adjacent layers parallel to each other, the two phases are α-U phase and δ-UZr₂ phase, respectively. The morphology of the second phase in the as-cast U-10wt%Zr alloy is approximately elliptical, unevenly distributed in the matrix, and composed of Zr precipitates. The research results are of great significance for further understanding the initial microstructure of U-Zr alloy and its correlation with irradiation behaviors.

Key words: U-Zr alloy, microstructure, phase composition, second phase

中图分类号:

TG27

赵勇, 吴裕, 刘超红, 伍晓勇, 方忠强, 强瑞. 铸态U-10wt%Zr合金的微观组织及第二相[J]. 金属热处理, 2025, 50(6): 73-78.

Zhao Yong, Wu Yu, Liu Chaohong, Wu Xiaoyong, Fang Zhongqiang, Qiang Rui. Microstructure and second phases of as-cast U-10wt%Zr alloy[J]. Heat Treatment of Metals, 2025, 50(6): 73-78.

参考文献

[1] Williams W J, Wachs D M, Okuniewski M A, et al. Assessment of swelling and constituent redistribution in uranium-zirconium fuel using phenomena identification and ranking tables (PIRT)[J]. Annals of Nuclear Energy, 2020, 136: 107016.
[2] Matthews C, Unal C, Galloway J, et al. Fuel-cladding chemical interaction in U-Pu-Zr metallic fuels: A critical review[J]. Nuclear Technology, 2017, 198(3): 231-259.
[3] Sohn Y H, Dayananda M A, Hofman G L, et al. Analysis of constituent redistribution in the γ (bcc) U-Pu-Zr alloys under gradients of temperature and concentrations[J]. Journal of Nuclear Materials, 2000, 279(2/3): 317-329.
[4] Hofman G L, Hayes S L, Petri M C. Temperature gradient driven constituent redistribution in U-Zr alloys[J]. Journal of Nuclear Materials, 1996, 227(3): 277-286.
[5] Qian Z, Xie X, Fu Y, et al. Investigation of swelling behaviors of U-10Zr metallic fuel in the low temperature regime via a cavitational void swelling model[J]. Journal of Nuclear Materials, 2022, 564: 153665.
[6] Pahl R G, Porter D L, Lahm C E, et al. Experimental studies of U-Pu-Zr fast reactor fuel pins in the experimental breeder reactor-ll[J]. Metallurgical Transactions A, 1990, 21: 1863-1870.
[7] Hofman G L, Pahl R G, Lahm C E, et al. Swelling behavior of U-Pu-Zr fuel[J]. Metallurgical Transactions A, 1990, 21: 517-528.
[8] Galloway J, Unal C, Carlson N, et al. Modeling constituent redistribution in U-Pu-Zr metallic fuel using the advanced fuel performance code BISON[J]. Nuclear Engineering and Design, 2015, 286: 1-17.
[9] Harp J M, Capriotti L, Chichester H J M, et al. Postirradiation examination on metallic fuel in the AFC-2 irradiation test series[J]. Journal of Nuclear Materials, 2018, 509: 454-464.
[10] Thomas J, Bengoa A F, Nori S T, et al. The application of synchrotron micro-computed tomography to characterize the three-dimensional microstructure in irradiated nuclear fuel[J]. Journal of nuclear materials, 2020, 537: 152161.
[11] Janney D E, Hayes S L. Experimentally known properties of U-10Zr alloys: A critical review[J]. Nuclear Technology, 2018, 203(2): 109-128.
[12] Carmack W J, Chichester H M, Porter D L, et al. Metallography and fuel cladding chemical interaction in fast flux test facility irradiated metallic U-10Zr MFF-3 and MFF-5 fuel pins[J]. Journal of Nuclear Materials, 2016, 473: 167-177.
[13] Harp J M, Porter D L, Miller B D, et al. Scanning electron microscopy examination of a fast flux test facility irradiated U-10Zr fuel cross section clad with HT-9[J]. Journal of Nuclear Materials, 2017, 494: 227-239.
[14] Sheldon R I, Peterson D E. The U-Zr (uranium-zirconium) system[J]. Bulletin of Alloy Phase Diagrams, 1989, 10(2): 165-171.
[15] Akabori M, Itoh A, Ogawa T, et al. Stability and structure of the δ phase of the U-Zr alloys[J]. Journal of Nuclear Materials, 1992, 188: 249-254.
[16] Lawson A C, Olsen C E, Richardson J W, et al. Structure of β-uranium[J]. Structural Science, 1988, 44(2): 89-96.
[17] Akabori M, Ogawa T, Itoh A, et al. The lattice stability and structure of delta-UZr₂ at elevated temperatures[J]. Journal of Physics: Condensed Matter, 1995, 7(43): 8249.
[18] Huber J G, Ansari P H. The superconductivity of BCC U-Zr alloys[J]. Physica B+C, 1985, 135(1/3): 441-444.
[19] Basak C, Prasad G J, Kamath H S, et al. An evaluation of the properties of as-cast U-rich U-Zr alloys[J]. Journal of Alloys and Compounds, 2009, 480(2): 857-862.
[20] Mukherjee S, Kaity S, Saify M T, et al. Evidence of zirconium nano-agglomeration in as-cast dilute U-Zr alloys[J]. Journal of Nuclear Materials, 2014, 452(1/3): 1-5.
[21] Hills B F, Butcher B R, Howlett B W, et al. The effect of cooling rate on the decomposition of the γ-phase in uranium-zirconium alloys[J]. Journal of Nuclear Materials, 1965, 16(1): 25-38.
[22] Bauer A A, Beatty G H, Rough F A, et al. The constitution of zirconium-uranium alloys containing oxygen or nitrogen[R]. Columbus: Battelle Memorial Institute, 1957.
[23] Rough F A, Bauer A A. Constitution of uranium and thorium alloys[R]. Columbus: Battelle Memorial Institute, 1957.
[24] Williams W J, Okuniewski M A, Vogel S C, et al. In situ neutron diffraction study of crystallographic evolution and thermal expansion coefficients in U-22.5at.%Zr during annealing[J]. The Journal of The Minerals, Metals and Materials Society, 2020, 72: 2042-2050.
[25] Kim K H, Oh S J, Kim S K, et al. Microstructural characterization of U-Zr alloy fuel slugs for sodium-cooled fast reactor[J]. Surface and Interface Analysis, 2012, 44(11/12): 1515-1518.
[26] McKeown J T, Irukuvarghula S, Ahn S, et al. Coexistence of the α and δ phases in an as-cast uranium-rich U-Zr alloy[J]. Journal of Nuclear Materials, 2013, 436(1/3): 100-104.
[27] Irukuvarghula S, Ahn S, McDeavitt S M. Decomposition of the γ phase in as-cast and quenched U-Zr alloys[J]. Journal of Nuclear Materials, 2016, 473: 206-217.
[28] Moore A P, Deo C, Baskes M I, et al. Atomistic mechanisms of morphological evolution and segregation in U-Zr alloys[J]. Acta Materialia, 2016, 115: 178-188.
[29] Rai A K, Subramanian R, Hajra R N, et al. Calorimetric study of phase stability and phase transformation in U-xZr (x= 2, 5, 10 wt pct) alloys[J]. Metallurgical and Materials Transactions A, 2015, 46: 4986-5001.
[30] Zhang Y, Wang X, Zeng G, et al. Microstructural investigation of as-cast uranium rich U-Zr alloys[J]. Journal of Nuclear Materials, 2016, 471: 59-64.
[31] Lehmann M J, Hills R F. Nomenclature proposee pour les phases des alliages d'uranium[J]. Journal of Nuclear Materials, 1960, 2(3): 261-268.
[32] Williams W J, Yao T, Sudderth L, et al. Phase identification and morphology in rolled and annealed U-22.5at.%Zr foils[J]. Materials Research Society Advances, 2021, 6(47): 1037-1042.
[33] Zegler S T. The Uranium-rich End of the Uranium-zirconium System[M]. Lemont: Argonne National Laboratory, 1962.
[34] Basak C B, Keswani R, Prasad G J, et al. Phase transformations in U-2wt%Zr alloy[J]. Journal of Alloys and Compounds, 2009, 471(1/2): 544-552.
[35] Di Lemma F G, Salvato D, Capriotti L, et al. Microstructure and phase evolution in the U-10Zr fuel investigated by in situ TEM heating experiments[J]. Journal of Nuclear Materials, 2023, 583: 154475.
[36] Hua Z, Yao T, Khanolkar A, et al. Intragranular thermal transport in U-50Zr[J]. Journal of Nuclear Materials, 2020, 534: 152145.
[37] 陈超, 白志勇. U-10wt%Zr合金熔炼工艺研究[C]//中国核学会2023年学术年会论文集. 2023.