Influence of Zn content on wettability of TiC cermet by AgCuZn alloy

Wetting experiments were performed on TiC cermet by AgCuZn alloy melted of AgCu eutectic powder and Zn powder with different ratios. It's shown that the smallest contact angle of 23.5° was obtained when the Zn content in AgCuZn alloy is 25%. The microstructure is respectively (Cu, Ni)+Ag(s.s)+Cu(s.s)/Ag(s.s)+Cu(s.s)/(Cu, Ni)/Ag(s.s)+Cu(s.s)+TiC cermet/TiC cermet from the near exterior surface of the alloy to the cermet. With the increasing of Zn content in the alloy, the morphology of (Cu, Ni) solid solution in the interface of alloy/TiC cermet changes from dispersive blocks to a continuous layer; dissolution and diffusion of the element in the interface were improved by evaporation of Zn in vacuum, which lead to decreasing of interface tension and increasing of surface tension of the liquid, and finally leads to a minimum of contact angle with increasing of Zn content.