Comparative assessment of loading-rate scaling versus mass scaling for predicting wrinkling in metal spinning

Explicit dynamic finite element simulations are used to study wrinkle formation in metal spinning. Full three-dimensional models remain computationally demanding and therefore often require numerical acceleration. This work directly compares two acceleration routes in explicit solvers, loading-rate scaling and mass scaling, and systematically examines their influence on wrinkle prediction. An identical process definition and toolpath are implemented in two simulation environments, and predictions are validated against experiments. Quasi-static fidelity is quantified through the kinetic-to-internal energy ratio, while accuracy is evaluated using the axial force history and wrinkle-related axial displacement measures, including the displacement field at the final stroke position and the peak-to-valley amplitude Δ with peak count. Results show that moderate acceleration, up to a factor of 10 for the present setup, maintains a low kinetic contribution and reproduces the experimental force trend and final wrinkle pattern. In contrast, aggressive scaling at a factor of 50 increases inertial contributions, amplifies force deviations, and reduces reliability of wrinkle predictions. These findings indicate that force histories, interpreted with energy diagnostics and surface metrics, provide a basis for validation and for selecting acceleration levels in wrinkle-focused spinning simulations. Equal nominal scaling factors do not necessarily correspond to equivalent inertial content across mechanisms.