Study On Corrosion Behaviors Of Ti₃SiC₂/Ti₃AlC₂ In Liquid Lead-bismuth Eutectic

Lead-cooled fast reactor(LFR)used liquid lead-bismuth eutectic(LBE)as the coolant,which causes serious corrosion problems to the structural materials in contact with it.Therefore,finding and developing structural materials with excellent resistance to LBE corrosion is the key way to solve this problem.As a new kind of radiation-resistant high-temperature structural material of its excellent properties of high temperature resistance,oxidation resistance,high strength and corrosion resistance,MAX phase material is currently one of the candidates for LFR structural materials.The corrosion performance in LBE serves as an important evidence of that can be applied to the LFR.Two typical MAX phase materials,Ti3SiC2 and Ti3AIC2,were immersed in static and dynamic LBE with saturated oxygen concentration at 500? from 500h to 3000h.The corrosion behaviors of Ti3SiC2 and Ti3AlC2 were analyzed by S Scanning Electron Microscope(SEM),Energy Dispersive X-Ray Spectroscopy(EDX),X-ray diffraction(XRD),Raman spectra,wettability test and mechanical properties.For the MAX phase material before and after corrosion,analyzed the surface and cross-sectional composition information of the material corrosion layer?the material surface hardness change information,combined with the contact angle change between the surface of the material and the LBE droplet analyzed the wettability of the corroded sample to LBE.The results show that the two materials have different degrees of corrosion in LBE.The Ti3SiC2 materials formed a double-layer corrosion structure composed of a diffusion layer and an oxide layer after being corroded in the LBE,while the Ti3AlC2 sample only formed a corrosion structure composed of a single diffusion layer.Through XRD and Raman Spectrum analysis,the main corrosion products of the transition layer and oxide layer are determined.The wettability of the corroded surfaces of the two materials to LBE is significantly worse.After corrosion,the surface of the two materials hardened to different degrees.The results showed that Ti3SiC2 has better resistance to LBE corrosion than Ti3AlC2.The results provided a basis for the choice of LFR structural materials.