Fundamental Study on Wettability of Pure Metal by Liquid Sodium

Liquid sodium is used as a coolant of a fast reactor owing to its high thermal conductivity and high melting temperature. Wettability is an important property for designing the apparatus of the fast reactor. It is well known that the wettability of liquid sodium changes owing to factors such as surface roughness and type of metal. This study proposes an atomic interaction between metal and liquid sodium related to wettability. The purpose of this study is to understand the wettability of pure metal by liquid sodium by using both experimental and theoretical approaches. High-purity metal plates of titanium, vanadium, iron, nickel copper, and molybdenum were used in the experiment. Wettability was evaluated using the contact angle obtained using the tangent method, and simple surface models were constructed for theoretical calculation. The contact angle was evaluated using two kinds of atomic bonds, and the result showed a relation between the contact angle and the atomic bond.