Alternative Control of an Electrically-Assisted Tensile Forming Process Using Current Modulation

Electrically-assisted forming is a technique whereby metal is deformed while simultaneously undergoing electric current flow. Using this process, electric current level becomes a new degree of freedom for process control. In this work we present some alternative control architectures allowing for new avenues of control using such a process. The primary findings are architectures to allow for forming at constant force and forming at constant stress levels by modulating electric current to directly control material strength. These are demonstrated in a tensile forming operation, and found to produce the desired results. Combining these control approaches with previous and contemporary efforts in modeling of the process physics will allow for system identification of material response properties and model-based control of difficult-to-observe process parameters such as real time temperature gradients.