Reversible interconnection by control of interface reactions

Reversible interconnection was proposed and realized by the combination of surface activated bonding and the precipitation of a brittle intermediate layer at the interface by heating. It was demonstrated by bonding samples of austenitic stainless steel (type 304) and Al. Stainless steel was successfully bonded to Al at room temperature through a thin intermediate layer composed of mainly Si and certain amounts of oxygen and carbon. The bonding strength was 20 MPa. Heating at 573 K for 2 hours had no effect on the bonding strength. Only the structure of the interface was changed after this heat treatment. Intermetallic compounds were formed at the original interface boundary when heating up to 823 K. Finally the joint was separated at the interface without applying any external force.