| A lithium reduction technique has been developed as an effective method for reducing the volume and radiation of the spent nuclear fuel, which can benefit to the disposal and management of the spent nuclear fuel. In this process, structural materials used in the technique undertake serious corrosion in molten LiCl-Li2O, which delayed the application of the new technique. To date, there have been few studies on the corrosion behavior of materials in molten LiCl-Li2O.In this paper we try to change the oxygen pressure in experiment and find out the infection of the corrosion behaviors by the oxygen pressure. immersion experiments are used to simulate service environment of structural material in the lithium reduction process. X-ray Diffraction (XRD) and Electron Probe Microanalysis (EPMA) are used to investigate the corrosion behaviors of 316L stainless steel in molten LiCl-Li2O in air and vacuum. It primarily discusses the corrosion mechanism and provides useful results and testing data for selecting materials and protective coatings under these conditions.The corrosion products of 316L stainless steel after corroded in molten LiCl and LiCl-Li2O are LiCrO2,LiFe5O8 and LiFeO2. When the consistence of the Li2O achieved 10% the corrosion products are LiCrO2 and single LiFeO2. The 316L stainless steel suffered more severe attack in the molten LiCl-Li2O mixture than in the molten LiCl at temperature 700℃.It is said that more Li2O in the molten salt more speed the corrosion is.The corrosion products of 316L stainless steel after corroded in molten LiCl and LiCl-Li2O in air and vacuum are the same:LiFe5O8 and LiCrO2. The weight loss of the two conditions increased with increasing time. The weight loss in vacuum condition was obviously less than that in air condition.It is because that in vacuum conditions the oxygen pressure is very low .It restrain the build of metal oxide and Li2O.As a result the corrosion speed was greatly reduced.The corrosion layer of 316L was non-protective.
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