Diffusion welding of Al-Cu-Mg series 2017 alloy.

Abstract

An investigation has been made of the diffusion welding of 2017 aluminum alloy which is very difficult to join by the conventional fusion-welding technique. In the present investigation the diffusion welding has been carried out in the temperature range above the solidus line where solid and liquid phases coexist, though it is a kind of solid-state welding. The purpose for this is to aid the intimate contact and the disruption of the tenacious oxide film at the bond interface by the formation of the liquid phase. As a result, the joint strength increased largely with raising the welding temperature above the solidus line and became much higher than that of the joint welded below the solidus line. The maximum tensile strength in the as-welded state, which was obtained at the welding temperature of 853K, was 270 MPa. It was observed with high-temperature-optical microscope that the liquid phase formed preferentially at the bond interface as well as at the grain boundary in the range between the solidus and liquidus lines. These results indicate that the liquid phase forming preferentially at the bond interface promoted effectively the bond process of diffusion welding. The maximum tensile strength was obtained when

Effect of Heating Rate on Al Bonding in Air by Inserted A5056 Disk

“…The volume fraction of the liquid phase influences the tensile strength of Al-3.42Cu-0.36Mg A2017 alloy. The maximum tensile strength was obtained when the volume fraction of the liquid was 2~3% [4]. Suitable Mg content of insert metal of Al alloy for diffusion bonding of Al was considered in previous study.…”