Improvement of corrosion properties in lead-bismuth by Al alloy coating on SUS316

Kurata, Yuji; Sato, Hidetomo*; Yokota, Hitoshi*; Suzuki, Tetsuya*

Liquid lead-bismuth is a candidate material used for accelerator driven systems and fast reactors. Development of corrosion resistant materials in liquid lead-bismuth is one of important research subjects to realize these systems. In this study, improvement of corrosion properties in lead-bismuth by Al alloy coating was investigated. Aluminum alloys were coated on 316SS using sheets made of Al, Ti and Fe powders, and laser heating. Adjustments of chemical composition in sheets and scanning rate of laser beam enabled us to control Al concentration in coating layers. The corrosion test was conducted at 550C for 3000h in oxygen-controlled lead-bismuth. As a result of the corrosion test, it was found that the coating with Al concentration of 5 to 8 mass% showed good corrosion resistance.