Hot Corrosion Behavior of High-Chromium, High-Carbon Cast Irons in NaCl-KCl Molten Salts

A study on the corrosion behavior of a series of experimental high-chromium (18.53-30.48 wt.%), high-carbon (3.82-5.17%) cast irons in NaCl-KCl (1 : 1M) at 670 degrees C has been evaluated by using weight loss technique and compared with a 304-type stainless steel. It was found that all castings had a higher corrosion rate than conventional 304SS and that the addition of Cr increased the degradation rate of the cast irons. Additionally, corrosion rate increased by increasing the C contents up to 4.29%, but it decreased with a further increase in its contents. Results are discussed in terms of consumption of the Cr2O3 layer by the melt.