ステンレス鋼-BC溶融混合物の系統的な粘度測定を目指したニッケルおよびステンレス鋼の粘度測定

Viscosity measurement of nickel and stainless steel aiming at systematic viscosity measurement for molten mixture of stainless steel and boron-carbide

小久保 宏紀*; 西 剛史*; 太田 弘道*; 山野 秀将   

Kokubo, Hiroki*; Nishi, Tsuyoshi*; Ota, Hiromichi*; Yamano, Hidemasa

ナトリウム冷却高速炉のシビアアクシデント評価手法の改良のため、ステンレス鋼と炭化ホウ素(SUS316L+BC合金)で構成される溶融混合物の粘度を取得することは重要である。本研究では、最初の段階として粘度計測装置の性能確認のため、溶融ニッケル(Ni)とステンレス鋼(SUS316L)の粘度を、るつぼ回転振動法により計測することにした。溶融NiとSUS316Lの粘度は1823Kまでを測定した。測定値のバラつきから、溶融NiとSUS316Lの測定誤差はそれぞれ4%と3%であった。また、溶融NiとSUS316Lの測定値は同様の組成をもつ文献値に近いことが分かった。さらに、SUS316L-BC合金の粘度も暫定的に計測できた。本研究によりNiとSUS316Lの粘度のフィッテイング式を得た。

It is important to obtain the viscosity of a mixed alloy consisting of molten stainless steel and boron-carbide (SUS316L + BC alloy) for the improvement of severe accident assessment methodology for sodium-cooled fast reactors. In this study, the viscosities of the molten nickel (Ni) and stainless steel (SUS316L) were measured by the oscillating crucible method to confirm the performance of the viscosity measurement apparatus as a first step. The viscosities of molten Ni and SUS316L melts were measured up to 1823 K. It was found that the measured viscosity values of molten Ni and SUS316L were estimated from the deviation of the experimental data, were 4% and 3%, respectively. It was also found that those of molten Ni and SUS316L were close to those of the literature values of molten Ni and similar composite stainless steels. Moreover, we tentatively measured the viscosity of molten SUS316L-5 mass%BC alloy. The fitted results of the viscosity for molten Ni and SUS316L were obtained.