Prediction of grain size for large-sized aluminium alloy 7050 forging during hot forming

摘要: A numerical approach for process optimization and microstructure evolution of lager-sized forging aluminium alloy 7050 was proposed, which combined a commercial FEM code Deform 3D with empirical models. To obtain the parameters constitutive equation dynamic recrystallization models 7050, isothermal compression tests samples were performed on Gleeble-1500 thermo-simulation machine in temperature range 250–450 °C strain rate 0.01–10 s−1, metallograph analysis carried out Leica DMIRM image analyzer. The simulation results show that central area billet occurs more easily than edge. Repetitious upsetting stretching processes make deform adequately. Among several e.g. upsetting, stretching, rounding flatting, is most effective way to increase refine billet. As steps increase, rises significantly average grain size reduces sharply. Recrystallized volume fractions parts final piece reach 100% 10 μm from initial value 90 μm.