Screening of Materials in NaCl–MgCl2 at 600 °C: A Comparative Study Leading to a New Corrosion-Resistance Criterion

Abstract The behavior of several materials in molten NaCl–MgCl 2 at 600 °C during 168 h was studied. In order to ensure the comparison of their respective corrosion resistance, a dedicated experimental setup and protocol were designed both for the control of the impurity level in the salt and for the corrosion testing. IN625 was used as a reference sample in every test, leading to a qualitative comparison between the different alloys. In these conditions, the SiC showed the best resistance, while TA6V and 316L suffered the most. For Ni-based alloys, Hastelloy G35 seemed to provide the best compromise despite its high chromium content. Thermodynamic calculations unveiled a strong link between the corrosion resistance of the alloy and a high dµCr/dnr leading to consider this as a new criterion for alloy design or selection.