In molten salt reactor (MSR), liquid fuel integrated with the molten salt coolant is used to improve the safety, resulting in the prevention of the loss-of-coolant accident (LOCA) that can occur in a pressurized water reactor (PWR). Because the structural materials used in MSRs are directly contacted with liquid fuel for a long time, they must have excellent corrosion resistance to the molten salt. Therefore, to examine the corrosion rates for Ni-based alloys in the molten salt, the corrosion experiments for alloy 600, alloy 617, and Hastelloy N were performed under LiCl molten salt at 635°C for 100 h in a glove box under Ar environment. Through a weight loss method for the three Nibased coupons before and after the corrosion tests, we evaluated their corrosion rates. Based on the results of weight loss for each alloy, we confirmed that Hastelloy N has the excellent corrosion resistance compared to the other alloys. Furthermore, the changes in the crystal structure and surface morphology with elemental distribution for the three alloys by corrosion in LiCl molten salt were analyzed, showing the variation in surface topography and the decrease in Cr element after corrosion experiments for all coupons.

• Hyeok Il Kim(Yeungnam University)
• Young-Sang Youn(Yeungnam University) Corresponding author