Superalloys are a group of alloys that exhibit excellent mechanical properties and corrosion resistance even at elevated temperatures. Among them is the nickel-based superalloy Inconel 718. Components made from Inconel 718 can also be produced by the selective laser melting process; however, heat treatment is required after the process, as undesirable phases that can affect the material's mechanical properties precipitate during solidification. In this master's thesis, the influence of solution annealing temperature and time on the microstructure development and phase precipitation during heat treatment was investigated in the temperature range of 1000 to 1200 °C, with annealing times of 10, 20, 30, 60, and 120 minutes. EBSD analysis was used to determine crystal grain size, recrystallization fraction, texture, and the fraction of twin boundaries in the microstructure. It was found that recrystallization began at 1050 °C between 10 and 20 minutes. At higher temperatures, recrystallization started between 0 and 10 minutes of annealing, and grain growth proceeded rapidly. The influence of annealing temperature on the mechanical properties of the material at room temperature was also studied. Properties were compared after annealing at 954, 1000, and 1100 °C, transversely and longitudinally to the build direction, to determine the anisotropy of mechanical properties. After annealing at 1000 °C, the yield strength was improved and ductility was reduced, while annealing at 1100 °C decreased the strength properties but improved ductility. Anisotropy remained after annealing at 1000 °C, whereas after annealing at 1100 °C, the directional dependence of strength properties was reduced.
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