Incremental micro-forming of stainless steel foil by high-speed water jet

Incremental micro-forming is a novel forming method that can produce miniature shell parts for small batch prototyping with customized design. In lieu of utilizing rigid tools to induce plastic deformation on the sheet metal, a high-speed water jet as an alternative was successfully applied in the incremental microforming process in this study. The influence of the jet trajectory and characteristics on the final geometry of features formed on stainless-steel foil was investigated. The incremental step/pitch of the trajectory and water jet pressure was found to have a dominant effect on the surface quality and depth of the part. Several different paths were designed to create cones, pyramids, polygonal pyramids and multi-level structures. Finite Element (FE) simulations were conducted in ABAQUS to simulate the entire manufacturing process. The numerical simulations were in good agreement with the experimental results in terms of geometry. The logarithmic strain in the radial direction after forming was also measured and compared to FE simulations.