Optimal Time-Temperature Curves for Heat-Treatable Aluminum Alloys

Aluminum alloys are widely used in industrial settings for their strength and corrosion resistance, and can be made even stronger through heat-treatment. Efficient heat treatment of aluminum alloys requires balancing mechanical performance, energy consumption, and processing time. This thesis investigates the optimal control of time-temperature profiles in an industrial furnace (model N 120/85 HA) for the heat-treatable alloy EN AW-6082 (Al-Mg-Si). A transient, physics-based model of the furnace is developed, capturing convective and radiative heat transfer, transient conduction through multilayered furnace walls, and the thermal interactions between furnace components. The model is implemented in MATLAB using an implicit time integration scheme. Calibration against experimental measurements demonstrates close agreement between predicted and observed temperatures, confirming the model’s predictive capability. Optimization over furnace air time-temperature curves is performed to minimize energy use and process duration while achieving target mechanical properties, with surrogate models incorporated to represent tensile strength, yield strength, and elongation. The proposed solution strategy successfully generates feasible temperature profiles across multiple operating scenarios, showing consistent, physically reasonable outcomes. These results demonstrate that the combination of calibrated modeling and trajectory-based optimization provides a reliable and flexible framework for efficient, data-driven heat treatment of aluminum alloys in industrial settings.