Microstructure evolution and wettability of Ag–Cu–Zn alloy on TiC–Ni cermet

Wetting of Ag–Cu–Zn alloy on TiC–Ni cermet was performed using a sessile drop method in vacuum and the interfacial microstructure was studied. A continuous (Cu, Ni) solid-solution layer was formed at the Ag–Cu–Zn/TiC–Ni cermet interface held at 810 °C for 10 min. According to the TEM results, an orientation relationship between the (Cu, Ni) solid-solution layer and the TiC particle at the interface was determined: TiC[42¯ 0]//(Cu, Ni) [0 2¯ 2], TiC(00 2¯)//(Cu, Ni)(111). As the temperature increased to 960 °C, the (Cu, Ni) solid-solution layer dissolved into the liquid alloy and changed from continuous to discontinuous. The continuing growth of the (Cu, Ni) solid-solution layer at the interface at 810 °C was controlled by the Ni diffusion process from the TiC–Ni cermet to the liquid alloy. The average contact angles of the Ag–Cu–Zn alloy and Ag–Cu alloy on the TiC–Ni cermet were 19° and 121.5° at 810 °C, respectively. And the temperature increase had little effect on the final contact angle.