• The Arrhenius constitutive model with coupled correction accurately predicts the flow stress of SLM-processed AlMgScZr alloy, with a correlation coefficient of 0.999 and an average absolute relative error of 2.766%.
• Hot processing maps at different strains identify stable and unstable regions, guiding optimal thermal deformation conditions for the alloy.
• Microstructural evolution during thermal deformation is temperature-dependent: dynamic recrystallization dominates at 300–360 °C, while dynamic recovery prevails at 390–500 °C.
• The study provides a foundation for optimizing hot working processes and predicting performance of SLM-fabricated high-strength aluminum alloys in high-temperature applications.