Thesis Type: Postgraduate
Institution Of The Thesis: Gazi University, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2021
Thesis Language: Turkish
Student: Murat ATKAYA
Supervisor: GÖKHAN KÜÇÜKTÜRK
Abstract:The effects of Electron Beam Welding of Al6061-T6 plate with 6 mm thickness was investigated numerically and experimentally. For the numerical study, 3D Computational Fluid Dynamics (HAD) model has been developed, compiled and solved with ANSYS 20 R1. The model was validated numerically and experimentally by comparing the size of the thermally affected areas. In this study, three different process parameters, voltage, current and speed parameters, were examined. In the voltage parameter, voltage values starting from 54kV with certain increases up to 60 kV have been shown by analysis and electron beam welding has also been applied on tensile specimen. The current parameter has been applied starting from 27mA up to 33mA. Finally, the other parameters were kept constant and the speed parameter was applied from 27 mm/s to 33 mm/s by both analysis and electron beam welding method. Depending on the effect of the electron beam current, the entire thickness can be melted by using a beam current over 30 mA at 60 volts and 30 mm/s welding speed according to the CFD model, and experimental studies show that using a beam current of more than 44 mA may cause defects on the bottom surface of the sample. At the threshold of these data, the effects of the parameters were investigated by using the Taguchi Method with Minitab 18.0 software. As a result of the studies, the electron beam source suitable parameter for the 6 mm thickness Al 6061-T6 material was determined as 60 volts, 30 mm / s and 42 mA, depending on the surface quality. The macrostructure analysis shows that there is a narrow heat affected zone and that barely clear boundaries can be seen between the base material and the heat affected zone. This situation was confirmed with 11% error both by analysis and test. In addition, micro hardness and tensile test were also examined in this study to verify the most appropriate electron beam source parameters to support all these data