Plasma and Fusion Research

Volume 19, 1405011 (2024)

Regular Articles


Effect of Ball Diameter on Mechanical Alloying Process for the Production of Dispersion Strengthened Tungsten
Hiroyuki NOTO, Yoshimitsu HISHINUMA and Takeo MUROGA
National Institute for Fusion Science, Toki, Gifu 509-5292, Japan
(Received 10 September 2023 / Accepted 11 January 2024 / Published 15 February 2024)

Abstract

Tungsten is candidate material for plasma facing armor. In our initial study, to improve the plasma facing tungsten on fusion divertor, a new oxide dispersion strengthened tungsten (ODS-W) has been developed using by REDOX (oxidation-reduction reaction) process between W and TiC, including titanium oxide as strengthening nano-particles in matrix, fabricated by mechanical alloying (MA)-hot isostatic pressing (HIP), which can inhibit the decrease of mechanical property even after recrystallization occurs. Our past studies showed that the condition of MA process affects the mechanical and the thermal properties of the products. In the present study, the optimal ball size to be used in the MA process of preparing ODS-W has been proposed by investigation of the relationship between different ball sizes and the MA effect, focusing the optimization of manufacturing process for DS-W. The evolutions of the lattice constant and microstructure were shown to indicate the progress of mechanical alloying. The effect of the ball size was interpreted as that of collision energy delivered by the weight of MA balls.


Keywords

tungsten, oxide dispersion strengthening, mechanical alloying

DOI: 10.1585/pfr.19.1405011


References

  • [1] M. Tokitani et al., Advanced multi-step brazing for fabrication of a divertor heat removal component, Nucl. Fusion 61, 046016 (2021).
  • [2] M. Fukuda et al., Microstructural development of tungsten and tungsten–rhenium alloys due to neutron irradiation in HFIR, J. Nucl. Mater. 455, 460 (2014).
  • [3] J. Reiser et al., Tungsten foil laminate for structural divertor applications, J. Nucl. Mater. 423, 1 (2012).
  • [4] G.-N. Luo, Q. Li et al., Coating materials for fusion application in China, J. Nucl. Mater. 417, 1257 (2011).
  • [5] S. Nogami et al., Effect of microstructural anisotropy on the mechanical properties of K-doped tungsten rods for plasma facing components, Fusion Eng. Des. 109-111, 1549 (2016).
  • [6] M. Fukuda et al., Microstructure development of dispersion-strengthened tungsten due to neutron irradiation, J. Nucl. Mater. 449, 213 (2014).
  • [7] H. Noto et al., Thermal change of microstructure and mechanical properties of dispersion strengthened tungsten, Nucl. Fusion 61, 116001 (2021).
  • [8] H. Kurishita et al., Development of Nanostructured Tungsten Based Materials Resistant to Recrystallization and/or Radiation Induced Embrittlement, Mater. Trans. 54, 456 (2013).
  • [9] H. Kurishita et al., Development of ultra-fine grained W-TiC and their mechanical properties for fusion applications, J. Nucl. Mater. 367-370, 1453 (2007).
  • [10] M. Rieth et al., Limitations of W and W-1%La2O3 for use as structural materials, J. Nucl. Mater. 342, 20 (2005).
  • [11] G. Yao et al., Excellent performance of W-Y2O3 composite via powder process improvement and Y2O3 refinement, Mater. Des. 212, 110249 (2021).
  • [12] M.V. Aguirre et al., Mechanical properties of tungsten alloys with Y2O3 and titanium additions, J. Nucl. Mater. 417, 516 (2011).
  • [13] H. Noto et al., Formation Mechanism of Nano-Strengthening Particles in Dispersion Strengthened W-Ti Alloys, Plasma Fusion Res. 15, 1205021 (2020).
  • [14] H. Kurishita et al., Development of re-crystallized W-1.1%TiC with enhanced room-temperature ductility and radiation performance, J. Nucl. Mater. 398, 87 (2010).
  • [15] M. Yamamoto et al., Reverse phase transformation from α to γ in 9Cr-ODS ferritic steels, J. Nucl. Mater. 417, 237 (2011).
  • [16] B. Ma et al., Development of Y2O3 dispersion strengthened Cu alloy using Cu6Y and Cu2O addition through the MA-HIP process, Fusion Eng. Des. 161, 112045 (2020).
  • [17] Q. Tang et al., Refinement of Oxide Particles by Addition of Hf in Ni-0.5 mass%Al-1 mass%Y2O3 Alloys, Mater. Trans. 51, 2019 (2010).
  • [18] T.H. Courtney et al., Process Modeling of Mechanical Alloying, Mater. Trans. 36, 110 (1995).
  • [19] G.B. Schaffer et al., The influence of collision energy and strain accumulation on the kinetics of mechanical alloying, J. Mater. Sci. 32, 3157 (1997).