Spot Welding between Aluminum Alloy and Low Carbon Steel by Friction Stirring

Abstract

The application of aluminum alloy, which is a typical lightweight material, has been expected to the construction of the transportation vehicle to achieve energy saving by reduction of its weight. However, the structure made of whole aluminum alloy had problems with low strength and high cost. Thus, hybrid structure made of Al alloy and steel is useful because of lightweight and higher strength. To construct the hybrid structure, it is necessary to weld between aluminum alloy and steel. However, the conventional welding methods, like brazing and mechanical fastening, have some problems such as low mechanical strength and low productivity. Also, it is difficult to weld Al alloy and steel by conventional fusion welding. In this study, spot welding between aluminum alloy and low carbon steel by friction stirring was carried out. Especially, optimization in welding conditions was carried out. Moreover, the effect of welding conditions on the joint strength and weld interface was studied. As a result, relatively higher tensile shear strength of the weld which was achieved at an optimum welding conditions was obtained. Temperature near weld interface measured by K type thermocouple during welding was found to be the value lower than the melting point of A5052. From the observation results on microstructure of weld interface, it was found that Fe/Al intermetallic compound layer was formed.

Fatigue behaviour of dissimilar friction stir spot welds between A6061-T6 and low carbon steel sheets welded by a scroll grooved tool without probe

“…joined 6008 aluminium alloy to steel and observed texture developed in the nugget 10,11 . Furthermore, Fukumoto et al 12–14 . and Aota et al 15 .…”

“…9 Bozzi et al joined 6008 aluminium alloy to steel and observed texture developed in the nugget. 10,11 Furthermore, Fukumoto et al [12][13][14] and Aota et al 15 joined aluminium alloy to steel by a flat tool without probe.…”

Fatigue behaviour of dissimilar friction stir spot weld between A6061 and SPCC welded by a scrolled groove shoulder tool

“…Bozzi et al joined 6008 aluminium alloy to steel and observed texture developed in the nugget [10,11]. Furthermore, Fukumoto et al [12][13][14] and Aota et al [15] joined aluminium alloy to steel by a flat tool without probe.…”

Spot welding between Aluminum Alloy and Several Kinds of Steels by Friction Stirring

“…Recently, solid phase welding between dissimilar metals by friction stirring was newly developed by authors 2 6) . We succeeded in spot welding between Al alloy and mild steel by friction stirring 7,8) .…”

“…The mechanical properties of weld joint were evaluated with tensile shear test and cross tensile test 7,8) . Torque, vertical load and temperature at weld interface were measured to comprehend the weld state.…”