Shinichi Kazui

Microstructural Characterization and Temperature Analysis in Friction Stir Welding of A383/5052 Dissimilar Aluminum Alloys

Microstructural characterization and temperature analysis have been performed in friction stir welding (FSW) of A383 and 5052 dissimilar aluminum alloys. Marked difference in microstructure was observed between joints with different arrangements of materials. The temperature at four points on each side of the joint line was measured during FSW in various conditions. In addition, an analytical model assumed that the work generated by the rotation of the tool led to the work for stirring materials and heat generation of the material and the tool. The temperature of the retreating side (RS) for the joint of the advancing side (AS):A383/RS:5052 was about 50K higher than that of AS, while the temperatures of AS and RS for the joint of AS:5052/RS:A383 were almost the same. The experimental temperature could be calculated reasonably by using the model with assumption of the work for stirring the material.

Relation between Strength and Microstructure in Friction Stir Welded Joints of A383 and A5052 Aluminum Alloys

Friction stir welding (FSW) was applied to joints of ASTM-A383 (Al- 11 %Si- 3%Cu-0.3Mg alloy) die casting and 5052 (Al- 2.5%Mg alloy) rolled sheets. A tensile specimen of FSWed A383 and 5052-0 alloys was broken in the base metal part of the latter alloy. Its tensile strength was about 195MPa, which was equal to that of 5052-0. On the other hand, a tensile specimen of FSWed A383 and 5052-H34 alloys was broken in heat affected zone (HAZ) or thermo-mechanical affected zone (TMAZ) of FSWed 5052 side. The joint showed the tensile strength of 220MPa, which was somewhat lower than the latter alloy strength, 245MPa. Vickers hardness test result showed that tensile specimens were broken at a portion of the lowest strength in the joint.