Abstract: An experimental investigation is carried out to study the FCI process as the high superheated molten metals contact with the subcooled water during the severe accident of nuclear reactors. In this study, the characteristics of FCI processes with different molten metals and initial temperatures are analyzed, which are beneficial for further studying of the complex boiling processes and heat transfer mechanisms on the high superheated surfaces of molten metals. The metal samples include aluminum, lead and bismuth, and the initial temperatures include 700℃, 750℃, 800℃, 850℃, 900℃ and 1000℃. According to this study, the effect of molten metal property on FCI process and the effect of initial temperature on the amount of vapor generated on the surface of molten metal are discussed. Moreover, the factors affecting the fast heat transfer between the high temperature molten metals and the subcooled water are discussed.