Numerical analysis of thermal phenomena during surface heat treatment of AlZn5.5MgCu aluminum alloy by GTA welding method

Abstract

In work, the modelling of a three-dimensional temperature field during surface modification of AlZn5.5MgCu aluminum alloy using GTAW (Gas Tungsten Arc Welding) technology is presented. GTAW is widely used for making welded joints using additional material (filler material). In the analyzed process, no additional material was used, and the effect of heat treatment was obtained by directly applying the electric arc to the surface of the material. The calculations were performed using Finite Element Method. The Goldak’s double ellipsoidal heat source model has been used in modelling. The thermal-mechanical properties of the material were assumed to depend on the temperature. The Workbench, DesignModeler, Mechanical, Fluent and CFD-Post modules of the ANSYS program were used for numerical simulations. In the description of the geometry of element heat treated, cube type elements were used, with density of grid in the heat affected zone. The temperature distributions in cross-sections of heated element as well as welding thermal cycles at selected points were analyzed. The results of numerical simulations were verified experimentally. Comparison of calculated and obtained in the experiment the fusion lines showed satisfactory compatibility.

Archives of Metallurgy and Materials

“…Due to this phenomenon, scandium can play a very profitable role in the welding process and is used as an alloying element in some filler wires [15,16]. considering the conventional welding techniques of aluminum alloys -tungsten inert gas (TiG) or metal inert gas (MiG), it can be stated that both are characterized by significant heat input and relatively wide welds [17][18][19][20][21][22]. For these reasons, the laser beam welding technique is far more effective, allowing to notably reduce the affecting of temperature on the welded workpieces, providing highly localized melting of material [23].…”