Friction stir welding of 2024-T3 aluminium alloy sheet with sheet pre-heating

Abstract

Friction stir welding is one of the most modern methods of joining metals and their alloys in the solid state. Ensuring the stability of working parameters requires a determination of the optimal welding parameters such as the rotational speed of the tool and the feed rate. This article presents the results of tests on welding of 1-mm-thick 2024-T3 aluminium sheet metal conducted in accordance with a PS/DK32 test plan. The welding tests were conducted on a universal milling machine, and the static strength tests were conducted on a static tensile-testing machine. In order to decrease the deformation of the joined sheets, some welding trials were also conducted with initial heating of the sheet metal. Therefore, a special fixture with a heated bed was developed. The tests show that the pre-heating of thin sheets that are friction stir welded leads to a reduction in the deformation size of the joined sheets. It was found that the smallest deformation of the joined sheets was observed in the case of joining sheets heated up to a temperature of 200 °C. Pre-heating of the joined sheets decreased the size of the deformations by 57.62 %.