Strong Mo/Cu interfacial bonding facilitated by consumable Ti interlayer

It is challenging to construct interfacial metallurgical bonding in Mo/Cu immiscible system because of the lack of mutual solubility. Here it was demonstrated that such problem can be effectively circumvented and robust Mo/Cu interfacial bonding can be achieved by diffusion bonding at 800 °C using a thin Ti interlayer. At the initial stage, bonding was made by forming MoTi solid solution (s.s) and TiCu intermetallic compounds (IMCs). The presence of IMCs was detrimental to joint integrity, leading to poor bonding strength. Prolonged bonding duration resulted in dilution of Ti and progressive elimination of TiCu IMCs. Ultimately, IMCs free joint exhibiting excellent interfacial bonding strength comparable with Cu base metal properties was obtained at bonding duration of 60 min.