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The corrosion behavior of 316 stainless steel (316 SS) in NaCl–KCl–FeCl3 molten salt and vapor was studied at 300°C for 150, 300, and 500 h in Ar. The weight change, the micromorphology, element distribution, and crystal structure of the 316 SS alloy were analyzed by scanning electron microscopy, energy‐dispersive spectroscopy, and X‐ray diffraction. 316 SS alloys suffered from weight loss, significant visible corrosion shedding, and corrosion holes. The corrosion holes and corrosion shedding block of the 316 SS alloys become more and more serious with the increase in corrosion time. The corrosion depth of the corroded 316 SS alloys in NaCl–KCl–FeCl3 molten salt and vapor for 500 h can even reach up to 20.0 and 14.0 μm, respectively. 316 SS alloys in NaCl–KCl–FeCl3 molten salts underwent a more serious corrosion attack than that in the NaCl–KCl–FeCl3 vapor at 300°C due to the strong oxidizing compound FeCl3 in the molten salt. It not only offers a new insight into the corrosion behavior of 316 SS alloys in the chloride salts and corresponding vapor but also enriches the corrosion databases of the chloride salts. [ABSTRACT FROM AUTHOR]

The corrosion behavior of GH3535 alloys in KCl–MgCl2 eutectic salts with or without magnesium (Mg) was investigated using the static immersion tests. The effect of purification treatment on the corrosion of GH3535 specimens was also evaluated by the different analysis. The KCl–MgCl2 salts purified with Mg and reducing service temperature can slow down the corrosion rate of GH3535 specimens. Infrared spectra results showed that purification treatment reduced the content of crystal water in the KCl–MgCl2 salts. The difference of hydrate content in KCl–MgCl2 salts and the diffusion rate of Cr in alloy are the main reasons for the change of GH3535 specimens corrosion rate. [ABSTRACT FROM AUTHOR]

The corrosion resistance of 316 stainless steel (316SS) in molten KCl-MgCl2 salts was studied through static immersion corrosion at high temperatures. Below 600 °C, the corrosion rate of 316SS increased slowly with increasing temperature. When the salt temperature rises to 700 °C, the corrosion rate of 316SS increases dramatically. The corrosion of 316SS is mainly due to the selective dissolution of Cr and Fe at high temperatures. The impurities in molten KCl-MgCl2 salts could accelerate the dissolution of Cr and Fe atoms in the grain boundary of 316SS, and purification treatment can reduce the corrosivity of KCl-MgCl2 salts. Under the experimental conditions, the diffusion rate of Cr/Fe in 316SS changed more with temperature than the reaction rate of salt impurities with Cr/Fe. [ABSTRACT FROM AUTHOR]

Understanding the corrosion of molten ZnCl2 on metal surfaces is significant for the corrosion protection of metals, sustainable use of molten salts, preparation of ZnO coatings, and so on. In this paper, surfaces of pure Ni, Cr, and Fe corroded by molten ZnCl2 were investigated. The results show that Ni suffered very slight corrosion, while Cr experienced more serious corrosion than Ni, but lighter corrosion than Fe. The morphology of the corrosion of Cr and Fe, respectively, presented pitting and intergranular corrosion characteristics. Furthermore, nanostructured ZnO coatings were obtained on the surfaces of Ni and Fe, but not on the surface of Cr. The ZnO coating on the Ni surface was doped with a small amount of Zn5(OH)8Cl2, and the ZnO coating on the Fe surface was doped with ZnFe2O4 and Zn2OCl2. The coatings on the Ni and Fe surfaces had an average thickness of 1.5 and 50 μm, respectively. [ABSTRACT FROM AUTHOR]

Understanding the corrosion of molten ZnCl2 on metal surfaces is significant for the corrosion protection of metals, sustainable use of molten salts, preparation of ZnO coatings, and so on. In this paper, surfaces of pure Ni, Cr, and Fe corroded by molten ZnCl2 were investigated. The results show that Ni suffered very slight corrosion, while Cr experienced more serious corrosion than Ni, but lighter corrosion than Fe. The morphology of the corrosion of Cr and Fe, respectively, presented pitting and intergranular corrosion characteristics. Furthermore, nanostructured ZnO coatings were obtained on the surfaces of Ni and Fe, but not on the surface of Cr. The ZnO coating on the Ni surface was doped with a small amount of Zn5(OH)8Cl2, and the ZnO coating on the Fe surface was doped with ZnFe2O4 and Zn2OCl2. The coatings on the Ni and Fe surfaces had an average thickness of 1.5 and 50 μm, respectively. [ABSTRACT FROM AUTHOR]