A Short Review of Electromagnetic Attractive Forming and Its Applications

Electromagnetic attractive forming (EMAF), as an emerging branch of electromagnetic forming (EMF), has attracted increasing attention due to its unique capacity to shape workpieces toward the coil, offering distinct advantages in forming small-diameter tubes, repairing surface dents, and strengthening hole fasteners. This review systematically classifies and elaborates on the two main approaches for generating electromagnetic attractive force: (1) methods based on dual-frequency discharge and (2) methods based on low-frequency discharge. For each category, the working principles, key technological configurations, experimental verifications, and application scenarios are comprehensively discussed. The dual-frequency discharge approach, implemented through sequential dual-capacitor, dual-coil, and novel single-power circuits, enables controllable attractive forces for sheet/tube forming and hole-fastener strengthening. The low-frequency discharge approach, utilizing ferromagnetic effects, attractive screen, or current-phase-difference mechanisms, extends EMAF to ferromagnetic and non-ferromagnetic materials. Finally, the existing challenges and future research directions are outlined, aiming to provide clear research guidance for the in-depth development and practical engineering application of EMAF technology.