Solid-State Diffusion Bonding of Titanium by Using Metal Salt Coated Aluminum Sheet

摘要

In this study, the effect of metal salt coating processing of aluminum surface on the bond strength of the solid-state diffusion bonded interface of titanium and aluminum has been investigated by SEM observation of the interfacial microstructures and fractured surfaces after tensile test. Aluminum surfaces were coated by boiling in 5% aqueous solution of NaOH for 90 s and 98% formic acid for 60 s. Bonding process was performed at a bonding temperature of 713 ~ 773 K under a load of 12 MPa for a bonding time of 900 s. As a result of the metal salt coating processing, high strength joint can be achieved with lower bonding temperature compared with unmodified joints. From this study, it is found out that metal salt coating processing is effective at removing oxide film and substitution to metal salt on the aluminum bonding surface.