The effects of rosette tool geometry on the rotational vibration-assisted incremental sheet forming process

Rotational Vibration-assisted Incremental Sheet Forming (RV-ISF) has emerged as a flexible process for manufacturing complex geometries with significant potential for wider applications. An experimental study was performed on a square pyramid geometry to investigate the effect of tool geometry and process parameters such as rotational speed and step size on the forming process of AA5251 H22 alloy sheets. The process was monitored using a suite of sensors to measure vibrations, force, and temperature, as well as machine tool data. Data from the eddy current sensor show that increasing rotational speed generally reduces vibration amplitude for RV-ISF tools by 27%, indicating more frequent but shorter-duration tool-sheet contact events at higher speeds, while finer step sizes increase vibration activity by 8%. Force and thermal measurements were also obtained, highlighting the influence of rotational speed, step size, and tool design on the thermo-mechanical response, with RV-ISF tools reducing frictional heating more effectively than conventional ISF tools by 22%. The results explain how tool design and process optimization can enhance vibrational and thermal softening in the incremental sheet forming process. This study contributes to the understanding of RV-ISF tool geometries by comprehensively monitoring the process with sensors and machine data and provides insights for improving part quality in incremental sheet metal forming.