This paper deals with the heat generation in the Al alloy Al2024-T3 plate under different rotating speeds and plunge speeds during the plunge stage of friction stir welding (FSW). A three-dimensional finite element model (FEM) is developed in the commercial code ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and Coulomb’s Law of friction. The heat generation in FSW can be divided into two parts: frictional heat generated by the tool and heat generated by material deformation near the pin and the tool shoulder region. Numerical results obtained in this work indicate a more prominent influence from the friction-generated heat. The slip rate of the tool relative to the workpiece material is related to this portion of heat. The material velocity, on the other hand, is related to the heat generated by plastic deformation. Increasing the plunging speed of the tool decreases the friction-generated heat and increases the amount of deformation-generated heat, while increasing the tool rotating speed has the opposite influence on both heat portions. Numerical results are compared with the experimental ones, in order to validate the numerical model, and a good agreement is obtained

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This paper presents experimental and numerical analysis of the change of temperature and force in the vertical direction during the friction stir welding of high-strength aluminium alloy 2024 T3. This procedure confirmed the correctness of the numerical model, which is subsequently used for analysis of the temperature field in the welding zone, where it is different to determine the temperature experimentally. 3D finite element model is developed using the software package Abaqus; arbitrary Lagrangian-Eulerian formulation is applied. Johnson-Cook material law and Coulomb's Law of friction are used for modelling the material behaviour. Temperature fields are symmetrical with respect to the welding line. The temperature values below the tool shoulder, i. e. in the welding zone, which are reached during the plunge stage, are approximately constant during the entire welding process and lie within the interval 430-502 °C. The temperature of the material in the vicinity of the tool is about 500 °C, while the values on the top surface of the welding plates (outside the welding zone, but close to the tool shoulder) are about 400 °C. The temperature difference between the top and bottom surface of the plates is small, 10-15 °C.

The aim of this work is to analyse the process of friction stir welding (FSW) of 3 mm thick aluminium plates made of high strength aluminium alloy -2024 T3, as well as to assess the mechanical properties of the produced joints. Friction StirWelding is a modern procedure which enables joining of similar and dissimilar materials in the solid state, by the combined action of heat and mechanical work. This paper presents an analysis of the experimental results obtained by testing the butt welded joints. Tensile strength of the produced joints is assessed, as well as the distribution of hardness, micro-and macrostructure through the joints (in the base material, nugget, heat affected zone and thermo-mechanically affected zone). Different combinations of the tool rotation speed and the welding speed are used, and the dependence of the properties of the joints on these parameters of welding technology is determined.

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