核融合施設向け、トリチウム封じ込め・放射線遮蔽用の柔軟複合材料を開発（Flexible Composite Offers Tritium Containment and Radiation Shielding for Fusion Facilities）

2026-09-02 合肥物質科学研究院（HFIPS）

Schematic illustration of the sealing and radiation shielding mechanism of micron spindle-shaped PbWO₄ filler-reinforced flexible silicone rubber for penetration holes in nuclear fusion facilities. (HUO Zhipeng)

＜関連情報＞

• https://english.hf.cas.cn/nr/rn/202609/t20260902_1189708.html
• https://www.sciencedirect.com/science/article/pii/S2238785426020107

核融合施設における貫通部封止および放射線遮蔽のための、微細構造制御されたPbWO₄充填剤強化フレキシブルシリコーンゴム Microstructure controlled PbWO4 filler-reinforced flexible silicone rubber for penetration sealing and radiation shielding in nuclear fusion facilities

Zhipeng Huo, Jie Zhang, Zuoyang Chen, Guoqiang Zhong
Journal of Materials Research and Technology  Available online: 29 July 2026
DOI:https://doi.org/10.1016/j.jmrt.2026.07.278

Abstract

Flexible silicone rubber (SR) composites doped with different reinforcing fillers are prepared for nuclear fusion facility penetration sealing and shielding against neutrons and gamma rays. Scanning Electron Microscope (SEM) reveals that micron spindle-shaped PbWO₄ fillers have much smaller particle sizes and more uniform size distribution. The experimental results indicate that the thermal resistance and mechanical performance of the spindle-PbWO₄ reinforced SR are superior to the other composites, with the maximum decomposition temperature of 490.1 °C, tensile strength of 0.92 MPa and compressive strength of 5.32 MPa. Moreover, the spindle-shaped PbWO₄ filler significantly reduces the thermal expansion behavior of the composite, which is more conducive to improving the thermal stability. This is attributed to its restraining effect on the thermal vibrations and relative displacements of the polymer chain of the matrix. Due to the ultraviolet absorption ability of PbWO₄, the tensile strength loss of the PbWO₄ filler-reinforced SR after 60 days of accelerated ultraviolet aging is significantly less than the other composites. SuperMC simulation demonstrates the superior synergistic neutron and gamma ray shielding capability of the spindle-PbWO₄/B₄C/SR composite and its effectiveness in reducing secondary gamma ray generation. At a thickness of 15 cm, the spindle-PbWO₄/B₄C/SR composite respectively achieves shielding rates of 93.13% against ²⁵²Cf neutrons and 82.76% against ¹³⁷Cs gamma rays, and it exhibits optimal shielding parameters (Σ = 0.167 cm⁻¹, μ_m = 0.080 cm²/g and μ = 0.117 cm⁻¹). The spindle-PbWO₄/B₄C/SR composite offers the best radiation shielding and meets the mechanical and airtightness requirements for sealing fusion device penetrations.