In this study, the inhomogeneous dealloying phenomenon during the liquid metal dealloying(LMD) was investigated using FeNi+Mg and(FeCo)Ni+Mg systems. For the FeNi+Mg system, the inhomogeneous dealloying and wetting of...In this study, the inhomogeneous dealloying phenomenon during the liquid metal dealloying(LMD) was investigated using FeNi+Mg and(FeCo)Ni+Mg systems. For the FeNi+Mg system, the inhomogeneous dealloying and wetting of Mg melt occurred along triple junction(TJ) and grain boundary(GB).Temperature increase enhances the inhomogeneous dealloying kinetics and leads to the formation of the plate-shaped abnormal ligaments at the GB region. The energy banlance between a GB energy(γGB)and solid-liquid interface energies(γsl) is the key factor governing the inhomogeneous dealloying and wetting. Particularly, the low-energy twin boundaries were unaffected by the inhomogeneous dealloying.Therefore, precursor microstructure is an important factor determining the final morphology of dealloyed material as well as its physical properties. In the case of the(FeCo)Niprecursor, all TJ and GB were stable against the preferred penetration of Mg melt from 600 ℃ to 800 ℃. It was concluded that a minor addition of alloying elements(VorCr) changes GB characteristics as well as γslof the precursor alloy.Consequently, this significantly influences dealloying mechanisms and final morphology of the dealloyed material. The current findings demonstrate the importance of GB engineering in the precursor materials for the technological application of liquid metal dealloying for the synthesis of advanced structural and functional materials.展开更多
基金supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT)(No.NRF-2021R1C1C1007645)the financial support provided by the International Collaboration Center,Institute for Materials Research (ICC-IMR),Tohoku University,Japanthe German Science Foundation under the Leibniz Program (Grant MA 3333/13-1)。
文摘In this study, the inhomogeneous dealloying phenomenon during the liquid metal dealloying(LMD) was investigated using FeNi+Mg and(FeCo)Ni+Mg systems. For the FeNi+Mg system, the inhomogeneous dealloying and wetting of Mg melt occurred along triple junction(TJ) and grain boundary(GB).Temperature increase enhances the inhomogeneous dealloying kinetics and leads to the formation of the plate-shaped abnormal ligaments at the GB region. The energy banlance between a GB energy(γGB)and solid-liquid interface energies(γsl) is the key factor governing the inhomogeneous dealloying and wetting. Particularly, the low-energy twin boundaries were unaffected by the inhomogeneous dealloying.Therefore, precursor microstructure is an important factor determining the final morphology of dealloyed material as well as its physical properties. In the case of the(FeCo)Niprecursor, all TJ and GB were stable against the preferred penetration of Mg melt from 600 ℃ to 800 ℃. It was concluded that a minor addition of alloying elements(VorCr) changes GB characteristics as well as γslof the precursor alloy.Consequently, this significantly influences dealloying mechanisms and final morphology of the dealloyed material. The current findings demonstrate the importance of GB engineering in the precursor materials for the technological application of liquid metal dealloying for the synthesis of advanced structural and functional materials.