The Corrosion Behavior of Multiphase Ceramic Protective Coatings on China Low Activation Martensitic Steel Surface in Flowing Liquid Lead-Bismuth Eutectic

Abstract

China low activation martensitic (CLAM) steel is the preferred candidate structural material for the Chinese international thermonuclear experimental reactor test blanket module (ITER TBM). Surface coating technology is often adopted to alter or improve the performance of materials. In CLAM steel, surface treatment plays a key role in rendering them appropriate for application in accelerator driven sub-critical system (ADS). Here, the authors prepare multiphase ceramic coatings on CLAM steel via laser in-situ reaction technology. The prepared multiphase ceramic coatings exhibit optimal corrosion resistance. The liquid lead-bismuth eutectic (LEB) corrosion resistance can be attributed to inferior wettability of interface between the LEB and multiphase ceramic coatings, faint shear force produced by LEB, and stable chemical and physical property of the coatings. Moreover, the irradiated specimens also display excellent corrosion resistance against helium ions irradiation. The CLAM steel is found to suffer significant corrosion in the flowing LEB. Such multiphase ceramic coatings as a protective layer on the ADS candidate structural materials CLAM steel surface exhibit the strongest LEB corrosion resistance, which can be applied to handle nuclear waste under extreme conditions.