Effect of metallic ion products on the corrosion of GH3535 alloy in a eutectic (Li, Na, K) F melt

Abstract

The effect of metallic ions and carbides on the corrosion of the GH3535 alloy was studied in a eutectic (Li, Na, K) F melt at 700 °C for different immersion times (20, 40, and 60 h). The results indicate that the average ΔV value between the carbides and the γ matrix is approximately 65 mV, which leads to galvanic corrosion between them at grain boundaries in the molten fluoride salt. Metallic ions produced by the corrosion of the alloy, such as Cr3+, Mo3+, and Ni2+, accelerated its corrosion in molten fluoride salts, which caused an “autocatalytic zone” to form within the corrosion layer during the exposure process.

Keywords

• GH3535 alloy
• Molten salts
• High-temperature corrosion