Theoretical and numerical analysis of incremental sheet forming by using high pressure water jet

Incremental sheet forming using water jet (ISF-WJ) is a new sheet metal forming process proposed in recent years. Few reports can be found on this process and some basic questions are unanswered, i.e., the water jet pressure required for plastic forming and the accuracy of this forming process. In this paper, an analytical model was developed to evaluate the size effect in the ISF-WJ process with respect to some key parameters, such as sheet thickness, part dimension, jet size and jet pressure. Three commonly used engineering sheet materials (aluminum, stainless steel and titanium) are studied in the analysis and the formability of water jet on these materials was evaluated. In addition, comparisons are made between the ISF-WJ and conventional ISF process with rigid tool based on finite element simulations. The result suggests that the dimensional accuracy of ISF-WJ may be controlled by a supporting back plate and ISF-WJ shows a better distribution of strain and thickness reduction than ISF process. It also provides a good reference for future ISF-WJ equipment design and development