Y2O3/(Cu–Me) systems (Me=Al, Ti): interface reactions and wetting

Wetting behavior and interface interaction between Y₂O₃ and Cu–alloys were investigated at 1,423 K. Pure copper does not wet yttria substrate but the wettability is significantly improved by additions of Al and Ti. Different interface structures were observed in the Y₂O₃/(Cu–Al) and Y₂O₃/(Cu–Ti) systems. Relatively deep crater was detected at the interface in the first system, while Cu alloying by Ti led to formation of a flat interface with a thin reaction layer. The results of the wetting experiments and the interface features were well accounted of by thermodynamic analysis of the Y₂O₃/(Cu–Me) systems.