Minimizing springback in AA6061 alloy during V-bending through process parameter optimization using a Full Factorial Design approach

Springback is a critical challenge in sheet metal forming, directly affecting dimensional accuracy and increasing rework costs in industrial production. This study systematically investigates springback behavior in AA6061 aluminum alloy during V‑bending using a Full Factorial Design (FFD) framework that simultaneously integrates die angle, sheet thickness, applied load, and holding time. A predictive statistical model was developed and validated, capturing both main and interaction effects with high accuracy ( 𝑅 2 = 0.9052, adjusted 𝑅 2 = 0.8831, predicted 𝑅 2 = 0.8427). Residual analysis confirmed normally distributed errors, and close agreement between predicted and experimental values validated model reliability. Mechanistic interpretation revealed that die angle governs geometric strain distribution, sheet thickness enhances bending stiffness, applied load controls plasticity, and holding time facilitates stress relaxation. Contour plots and response surfaces highlighted strong interactions between sheet thickness and applied load, while die angle and holding time exerted secondary effects. Optimization identified the parameter set of 60° die angle, 2.4 mm sheet thickness, 8 kN applied load, and 60 s holding time as the most effective condition, yielding a minimum springback of 1.082° with a desirability score of 0.998. The findings provide a robust predictive tool for minimizing springback, offering practical guidance for die design, dimensional accuracy improvement, and cost reduction in industrial forming operations.