Forming process design involving die design and optimization of forming conditions can be carried out successfully when the flow condition of a material in a plastic forming process is known. Logical forming simulation using the finite element method and physical forming simulation using the visioplasticity method have been utilized to visualize the material flow condition in a plastic forming process such as extrusion and forging. However, real-time measurement of the three-dimensional non-steady-state plastic flow field has not been carried out yet. The authors developed a new measurement system constructed with a model material (wax containing powders) representing the deformation characteristic of an actual metallic material, tiny steel particles embedded in the model material as the tracers of material flow, dies made of epoxy resin and a stereo X-ray unit. Then, the non-steady-state material flow condition could be measured using the developed system with regard to process time and visualized in the three-dimensional coordinate system. To demonstrate the system performance and utility, the material flow condition in the forging process of a scroll rotor made of magnesium alloy AZ31 was measured and visualized using the developed system and a model material of AZ31.
High-precision measurement and identification of deformation in metal forming is significant. In this study, a die-embedded sensing system with micro-semiconductor sensors fabricated using semiconductor process technology was developed. The die-embedded sensing system is a new sensing tool for measuring complex phenomena by monitoring stresses in the die during the process. As a case study, we applied the die-embedded sensing system to the V-bending process. A microsensor for the measurement of the load and bending angle during processing was designed and fabricated. The results show that the new sensing system has advantages over conventional sensors.