Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
권호 표지
DOI QR코드

DOI QR Code

Manufacturing and testing of flat-type divertor mockup with advanced materials

  • Nanyu Mou (Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences) ;
  • Xiyang Zhang (Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences) ;
  • Qianqian Lin (Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences) ;
  • Xianke Yang (Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences) ;
  • Le Han (Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences) ;
  • Lei Cao (Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences) ;
  • Damao Yao (Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences)
  • Received : 2022.12.24
  • Accepted : 2023.03.21
  • Published : 2023.06.25
Download PDF
⟨ Previous Next ⟩

Abstract

During reactor operation, the divertor must withstand unprecedented simultaneous high heat fluxes and high-energy neutron irradiation. The extremely severe service environment of the divertor imposes a huge challenge to the bonding quality of divertor joints, i.e., the joints must withstand thermal, mechanical and neutron loads, as well as cyclic mode of operation. In this paper, potassium-doped tungsten (KW) is selected as the plasma facing material (PFM), oxygen-free copper (OFC) as the interlayer, oxide dispersion strengthened copper (ODS-Cu) alloy as the heat sink material, and reduced activation ferritic/martensitic (RAFM) steel as the structural material. In this study, a vacuum brazing technology is proposed and optimized to bond Cu and ODS-Cu alloy with the silver-free brazing material CuSnTi. The most appropriate brazing parameters are a brazing temperature of 940 ℃ and a holding time of 15 min. High-quality bonding interfaces have been successfully obtained by vacuum brazing technology, and the average shear strength of the as-obtained KW/Cu and ODS-Cu alloy joints is ~268 MPa. And a fabrication route for manufacturing the flat-type divertor target based on brazing technology is set. For evaluating the reliability of the fabrication technologies under the reactor relevant condition, the high heat flux test at 20 MW/m2 for the as-manufactured flat-type KW/Cu/ODS-Cu/RAFM mockup is carried out by using the Electron-beam Material testing Scenario (EMS-60) with water cooling. This paper reports the improved vacuum brazing technology to connect Cu to ODS-Cu alloy and summarizes the production route, high heat flux (HHF) test, the pre and post non-destructive examination, and the surface results of the flat-type KW/Cu/ODS-Cu/RAFM mockup after the HHF test. The test results demonstrate that the mockup manufactured according to the fabrication route still have structural and interfacial integrity under cyclic high heat loads.

Keywords

Acknowledgement

This work was supported by Comprehensive Research Facility for Fusion Technology Program of China [2018-000052-73-01-001228]; and the National MCF Energy R&D Program [2018YFE0312300].

References

  1. N. Baluc, K. Abe, J.L. Boutard, et al., Status of R&D activities on materials for fusion power reactors, Nucl. Fusion 47 (2007) S696, https://doi.org/10.1088/0029-5515/47/10/S18.
  2. M. Rieth, S.L. Dudarev, S.M.G. De Vicente, et al., Recent progress in research on tungsten materials for nuclear fusion applications in Europe, J. Nucl. Mater. 432 (2013) 482-500, https://doi.org/10.1016/j.jnucmat.2012.08.018.
  3. Y.X. Wan, J.G. Li, Y. Liu, et al., Overview of the present progress and activities on the CFETR, Nucl. Fusion 57 (2017), 102009. https://10.1088/1741-4326/aa686a.
  4. J.G. Li, Y.X. Wan, Present state of Chinese magnetic fusion development and future plans, J. Fusion Energy 38 (2019) 113-124, https://doi.org/10.1007/s10894-018-0165-2.
  5. S.J. Zinkle, L.L. Snead, Designing radiation resistance in materials for fusion energy, Annu. Rev. Mater. Res. 44 (2014) 241-267, https://doi.org/10.1146/annurev-matsci-070813-113627.
  6. A. Tincani, M.G. D'Angelo, P.A. Di Maio, et al., Hydraulic characterization of the full scale divertor cassette prototype, Fusion Eng. Des. (2011) 1673-1676, https://doi.org/10.1016/j.fusengdes.2010.12.006.
  7. J.H. You, R. Villari, D. Flammini, et al., Nuclear loads and nuclear shielding performance of EU DEMO divertor: a comparative neutronics evaluation of two interim design options, Nucl. Mater. Energy. 23 (2020), 100745, https://doi.org/10.1016/j.nme.2020.100745.
  8. J. Linke, High heat flux performance of plasma facing materials and components under service conditions in future fusion reactors, Fusion Sci. Technol. 2006 (2006) 455-464, https://doi.org/10.13182/FST06-A1144.
  9. H. Bolt, V. Barabash, G. Federici, et al., Plasma facing and high heat flux materialseneeds for ITER and beyond, J. Nucl. Mater. 307 (2002) 43-52, https://doi.org/10.1016/S0022-3115(02)01175-3.
  10. S.J. Zinkle, Advanced materials for fusion technology, Fusion Eng. Des. 74 (2005) 31-40. https://doi.org/10.1016/j.fusengdes.2005.08.008
  11. Zhiwei Pan, Shenghong Huang, Menglai Jiang, In-situ measurements of deformation to fatigue failure on a flat-type divertor mock-up under high heat flux loads by 3D digital image correlation, Nucl. Fusion 61 (2021), 026018, https://doi.org/10.1088/1741-4326/abcc18.
  12. Y. Xu, C.Y. Xie, S.G. Qin, et al., Preliminary R&D on flat-type W/Cu plasma-facing materials and components for experimental advanced superconducting tokamak, Phys. Scripta T159 (2014), 014008, https://doi.org/10.1088/0031-8949/2014/T159/014008.
  13. H. Bolt, V. Barabash, W. Krauss, et al., Materials for the plasma-facing components of fusion reactors, J. Nucl. Mater. 329 (2004) 66-73, https://doi.org/10.1016/j.jnucmat.2004.04.005.
  14. J.W. Davis, K.T. Slattery, D.E. Driemeyer, et al., Use of tungsten coating on iter plasma facing components, J. Nucl. Mater. 233 (1996) 604-608, https://doi.org/10.1016/S0022-3115(96)00209-7.
  15. J. Linke, J. Du, T. Loewenhoff, et al., Challenges for plasma-facing components in nuclear fusion, Matter Radiat. Extremes 4 (2019), 056201, https://doi.org/10.1063/1.5090100.
  16. A. Giannattasio, S.G. Roberts, Strain-rate dependence of the brittle-to-ductile transition temperature in tungsten, Philos. Mag. A 87 (2007) 2589e2598, https://doi.org/10.1080/14786430701253197.
  17. Y.C. Wu, Q.Q. Hou, L.M. Luo, et al., Preparation of ultrafine-grained/nanostructured tungsten materials: an overview, J. Alloys Compd. 779 (2019) 926-941, https://doi.org/10.1016/j.jallcom.2018.11.279.
  18. X. Ma, F. Feng, X. Zhang, et al., Effect of potassium bubbles on the thermal shock fatigue behavior of large-volume potassium-doped tungsten alloy, Nucl. Fusion 62 (2022), 126062, https://doi.org/10.1088/1741-4326/ac9a5b.
  19. S.J. Zinkle, A. Moslang, T. Muroga, et al., Multimodal options for materials research to advance the basis for fusion energy in the ITER era, Nucl. Fusion 53 (2013), 104024, https://doi.org/10.1088/0029-5515/53/10/104024.
  20. M. Rieth, S.L. Dudarev, S.M.G. de Vicente, Review on the EFDA Programme on Tungsten Materials 417 (2011) 463-467.
  21. Z.M. Xie, R. Liu, T. Zhang, et al., Achieving high strength/ductility in bulk W-Zr-Y2O3 alloy plate with hybrid microstructure, Mater. Des. 107 (2016) 144-152, https://doi.org/10.1016/j.matdes.2016.06.012.
  22. X. Ma, X. Zhang, T. Wang, et al., Large-scale potassium-doped tungsten alloy with superior recrystallization resistance, ductility and strength induced by potassium bubbles, J. Nucl. Mater. 559 (2022), 153450, https://doi.org/10.1016/j.jnucmat.2021.153450.
  23. M. Li, S.J. Zinkle, Compr. Nucl. Mater. 4 (2012) 667-690. https://doi.org/10.1016/B978-0-08-056033-5.00122-1
  24. N. Mou, X. Zhang, Q. Lin, et al., Fabrication and performance tests for ODS Cu/CLF-1 clad plate as divertor heat sink via explosive welding, IEEE Trans. Plasma Sci. 50 (2022) 4753-4758, https://doi.org/10.1109/TPS.2022.3210025.
  25. S.M.S. Aghamiri, N. Oono, S. Ukai, et al., Microstructure and mechanical properties of mechanically alloyed ODS copper alloy for fusion material application, Nucl. Mater. Energy. 15 (2018) 17-22, https://doi.org/10.1016/j.nme.2018.05.019.
  26. X. Chen, S. Qin, Q. Wang, et al., Fatigue life prediction of hypervapotron for CFETR divertor, Fusion Eng. Des. 174 (2022), 112985, https://doi.org/10.1016/j.fusengdes.2021.112985, 2022.
  27. B.C. Odegard, B.A. Kalin, A review of the joining techniques for plasma facing components in fusion reactors, J. Nucl. Mater. 233 (1996) 44-50. https://doi.org/10.1016/S0022-3115(96)00303-0
  28. N. Mou, L. Han, D. Yao, Study on the heat absorption coefficient of tungsten as the plasma-facing material for the upgraded EAST lower divertor, IEEE Trans. Plasma Sci. 50 (2022) 2455-2459, https://doi.org/10.1109/TPS.2022.3185715.
  29. T. Hirai, F. Escourbiac, V. Barabash, et al., Status of technology R&D for the ITER tungsten divertor monoblock, J. Nucl. Mater. 463 (2015) 1248-1251, https://doi.org/10.1016/j.jnucmat.2014.12.027.
  30. K. Ezato, S. Suzuki, Y. Seki, et al., Progress of ITER full tungsten divertor technology qualification in Japan, Fusion Eng. Des. 98 (2015) 1281-1284, https://doi.org/10.1016/j.fusengdes.2015.03.009.