Reactive Wetting of Metallic Plated Steels by Liquid Sodium

Abstract

Sodium wetting experiments were performed to investigate the reactive wetting of metallic plating materials by liquid sodium at 250°C for the ultrasonic sensor of the under-sodium viewer. SUS304 stainless steel specimens were electrolytically plated with four metallic materials (nickel, palladium, gold, and indium) that have different solubilities in sodium, and the spreading velocity of sodium droplets on the metallic plated specimens was measured. It was confirmed that the spreading velocity increased as the solubility increased, and the constant α on the spreading velocity on the plated specimens was unique for the plating materials and was proportional to the logarithm of the solubility of the plating materials. Furthermore, it is considered possible to select plating materials based on solubility from the result of this study.