Presented master's thesis focuses on analysis of simulation results of aluminium alloy extrusion billet preheating and spray cooling simulations. Mentioned processes are directly connected to the bulk metal forming processing named hot extrusion. The main products of hot aluminium alloy extrusion are rods, tubes and profiles. Pre-processing and the simulation of pre-processing, which is considered as a pre-extrusion heat treatment of preheating, spray cooling and general cooling, provides the ability to heat the material to extrusion temperature, dissolve of intermetallic phases and the effect of heat transfer to and from the preheated material before the extrusion process takes place. Post-extrusion heat treatment includes water quenching of extruded material, which sets basis for further natural or artificial ageing. Both mentioned contribute to mechanical properties due to precipitation hardening effect. Heat treatment pre- and post-extrusion processing greatly affects the properties of the material, both microstructural and mechanical properties, subsequently also the properties of extruded product. The master's thesis's focuses on simulations of preheating, spray cooling and cooling of the billet material pre-extrusion. Pre-extrusion heat treatment finite element method simulations provide broader information of the temperature field on the surface and inside the billet. The model accuracy is be supported with result of temperature measurements, performed before the extrusion. Calibration of models is carried out with the adjustment of the main process parameters in order to achieve realistic response of the simulation models.
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