Compatibility between the Molten Mg-25Al-15Zn-14Cu Alloy and Stainless Steel for Phase-Transformation Thermal Storage Facility

The compatibility of molten Mg-25Al-15Zn-14Cu alloy with several candidate vessel shell materials such as 304 stainless steel, 201 stainless steel for phase-transformation thermal storage facility were evaluated by means of immersion corrosion test at 500°C for 1000 h. The microstructure, element distribution and surface corrosion layer structure and phase composition of the cross section of corrosion samples were analyzed by using optical microscope (OM), X-ray diffraction (XRD) and electron microprobe analysis (EPMA). The results show that two kinds of stainless steel have good compatibility in the molten Mg-25Al-15Zn-14Cu alloy. The thickness of the erosion layer is less than 0.1mm. The corrosion interface of corrosive material in the molten Mg-25Al-15Zn-14Cu alloy can be divided into the base layer, the diffusion layer, the corrosion layer, segregation layer (C, Cr, Ni), linked coating layer.