Thermo–Mechanical modeling and experimental validation of Heat-Assisted Single-Point incremental forming of AA1050 complex Thin-Shell Components: Process optimization and Mechanistic Insights

Heat-assisted single-point incremental forming (HA-SPIF) has emerged as a promising approach for manufacturing complex thin-walled components by improving material formability and reducing forming loads. Nevertheless, the coupled influence of thermal conditions, constitutive behavior, and key process parameters on thickness evolution and geometric accuracy remains insufficiently quantified for commercially pure aluminum alloys under non-isothermal deformation conditions. This study develops an integrated experimental–numerical framework to investigate the HA-SPIF process applied to AA1050 complex cranial thin-shell components. A resistive heating system was first analyzed through finite-element thermal simulations and experimentally validated using in-situ temperature measurements, enabling accurate calibration and control of the workpiece temperature during forming. The calibrated thermal conditions were then incorporated into thermo-mechanically coupled simulations employing several temperature-dependent constitutive models, including the Swift, Voce, and Kim–Tuan formulations. Comparative validation indicates that the Kim–Tuan model provides the most accurate prediction of thickness distribution and geometric deviation, with a minimum thickness prediction error of approximately 2.92% compared with experimental measurements. The experimental results further demonstrate that increasing the forming temperature from 25 °C to 250 °C reduces the average forming force by 36.20% and the maximum forming force by 26.53%, reflecting the significant influence of thermal softening on deformation resistance. In addition, heat-assisted forming improves thickness uniformity and reduces geometric deviation from the target profile, with the maximum deviation limited to approximately 0.45 mm under optimized conditions. A comprehensive parametric investigation identifies an optimal parameter combination of T = 150 °C, vertical step size tz = 1.0 mm, and tool diameter D = 12 mm, which achieves improved thickness distribution, reduced forming loads, and enhanced geometric fidelity. The close agreement between numerical predictions and experimental results confirms the reliability of the proposed thermo-mechanical modeling framework. This work provides new quantitative insight into the thermo-mechanical mechanisms governing heat-assisted SPIF and establishes a practical strategy for optimizing process parameters in the precision forming of complex thin-walled aluminum components.