Wettability of Al₂O₃ by liquid Cu as influenced by additives and partial transient liquid-phase bonding of Al₂O₃

The effect of additions (Cr, Ni and 80Ni·20Cr alloy) on the wetting characteristics of liquid Cu on Al₂O₃ has been studied using a sessile drop method in a vacuum at 1150°C. Through the use of microdesigned multilayer Cu/80Ni·20Cr/Cu interlayers, PTLP (Partial Transient Liquid-Phase) bonding of Al₂O₃ has been achieved in a vacuum at 1150°C. These results demonstrate that the bonding temperature, the dissolution of Cr into liquid Cu film improved the wettability of liquid Cu film on Al₂O₃ and facilitate the formation of reliably strong joint PTLP bonded Al₂O₃ using Cu/80Ni·20Cr/Cu interlayer.