Molten carbonate corrosion of a 13-Cr ferritic stainless steel protected by a perovskite conversion treatment: Relationship with the coating microstructure and formation mechanism

► Perovskite conversion coating for corrosion protection of a 13-Cr stainless steel. ► Coating formation mechanism studied in two different molten salt bath compositions. ► Oxide basicity of the salt bath must be controlled to avoid substrate corrosion. ► Coating formation mechanism affected both perovskite grain size and MCFC performance. ► Precursor-template coating synthesis promoted excellent MCFC corrosion protection.