Experimental Analysis on Granular Media-Based Tube Forming with Active Axial Feed

Production of high strength, high stiffness, and safety-relevant profile parts is feasible through the sequence of media-based forming and in-die quenching. As forming media, solid granular media have been recently introduced. In this work, the granular media tube press hardening process with additional axial feeding is investigated in order to enhance the tube thickness distribution and to enlarge the process window. The experiments show that, compared to the process with frictional feed, the limits for insufficient forming and wrinkling are unaffected by the change of the feeding system, while the area for intolerable thinning is reduced. Additionally, through the new feeding system, a higher degree of design freedom could be achieved, e.g., shoulder angles of 90° are possible. Furthermore, for the design of the process, an advanced FEM simulation has been developed, which is based on the Drucker–Prager cap model and covers also the thermal interactions.