Interfacial reactions between liquid Ga and solid Au

[Display omitted] •Interfacial reactions between liquid Ga and solid Au were investigated.•Only one intermetallic phase, AuGa2, was formed from room temperature to 150 °C.•Time exponents for the AuGa2 growth were determined to be 0.91–2.01.•Grain boundary diffusion of Ga was assumed to be the rate-determining step for AuGa2 growth. Interfacial reactions between liquid Ga and solid Au were investigated from room temperature to 150 °C. It was found that only one intermetallic phase, AuGa2, was formed at the Ga/Au interface at all temperatures. During storage, the newly formed fresh AuGa2 phase continuously nucleated and grown at room temperature on the preformed AuGa2/Au interface under supercooled liquid Ga. Time exponents for the AuGa2 growth were measured to be 0.91–1.44 and 2.01 at room temperature to 125 °C and 150 °C, respectively, with an activation energy of 85.4 kJ/mol at 100–150 °C. Diffusion of Ga atoms through the AuGa2 grain boundaries was assumed to be the rate-determining step for AuGa2 growth.