Insights into the surface behavior of Inconel 617 and Inconel 625 material in molten salt

摘要

High-temperature nickel alloys must be compatible with molten salt phase-change materials (PCM) for future concentrating solar power (CSP) systems. This work intends to identify the relation between the corrosion behaviour of Inconel 617 and 625 in a Na_2SO_4-45 wt% Diatomite eutectic molten salt mixture at 800 ℃ under different durations like 160 h, 240 h, and 480 h. Thermogravimetry analysis was carried out to evaluate the corrosion rate. Further SEM/EDS and XRD analysis were carried out to evaluate the mechanism of corrosion. High corrosion rate of 8.34 and 7.46 mm/y attained for Inconel 617 and Inconel 625, respectively at maximum immersion duration (480 h).