From feasible to useable incremental sheet forming processes

Abstract Many promising incremental forming processes have been proposed in the scientific literature, but only few have found their path to industrial use. The main reason for the disappointing success rate is given by the failure to comply with geometrical requirements. The paper at hand proposes a stepwise approach to enhance the geometrical properties and thereby potential usability of an incremental sheet forming process. The mode of deformation and the effectiveness of the compensation are identified as key aspects. The path from feasibility to usability is exemplified by the novel incremental forming process hole-rolling. During this process, a roller forms a one- or double-sided collar around a hole in a spiral movement, where the contour of the formed part can be circular or an individual geometry, like a polygon shape. The process characteristics are analysed using two different forming tools, which demonstrate different possible process routes. A model-based compensation method, which is based on forming force and an analytical model of the forming tool, is developed and verified using two different geometries, thereby demonstrating its usability.