Experimental investigation of welding of aluminum alloys profiles and wrought plate by FSW

Abstract

This paper describes an attempt to reduce some of the defects and to produce good quality welds when weld-ing Al-Mg-Si alloy profiles EN AW-6005 or EN AW-6063 and Al-Mg alloy wrought plate EN AW-5754 in butt joints of thickness of 3 mm by using mechanized Friction Stir Welding (FSW). The weld joints were performed on mate-rials partly cleaned (aluminum oxide elimination) and not cleaned. The defects when welding these profiles and a plate can come as a result of lack of penetration, incorrect setting of the process parameters, and wrong rotational direction of the tool. However, the sources of the defects in FSW remain uncertain.
The effect of the main welding process parame-ters and the mechanical properties of these aluminum alloy welds were studied in the oxide and not oxide portions. From the macro-sections and the mechanical properties tests, it was drawn that the rotational direction can change quality of the weld. This is due to the unusual stirring of the weld pool which brings about differences in the hard-ness of the weld joints. The aluminum oxide particles do not have a great influence on tensile strengths, but if more productivity is needed, then oxide removal is recom-mended.