Corrosion monitoring of ferritic-martensitic steels in molten salt environments for CSP applications

Abstract

In the present work, the behaviour of a ferritic-martensitic steel, VM12, in Solar Salt was monitored by EIS. To this end corrosion tests at 580°C were carried out for 1000h. According to the EIS results, a diffusion-controlled reaction occurred during test, which indicates the formation of a porous corrosion layer. The EIS results also shown a corrosion rate of 50μm·year-1 after 1000h of testing. Results obtained by EIS were in agreement with the ones obtained by gravimetric and SEM-EDX analysis. Thus, results showed the possible suitability of EIS for monitoring corrosion processes in real-time of steels in CSP plants.