Experimental study of high-frequency vibration assisted micro/mesoscale forming of metallic materials

Micromesoscale forming is a promising technology for mass production of miniature metallic parts. However, fabrication of micromesoscale features leads to challenges due to the friction increase at the interface and tool wear from highly localized stress. In this study, the use of high-frequency vibration for potential application in micromesoscale forming has been investigated. A versatile experimental setup based on a magnetostrictive (Terfenol-D) actuator was built. Vibration assisted micromesoscale upsetting, pin extrusion and cup extrusion were conducted to understand the effects of workpiece size, excitation frequency, and the contact condition. Results showed a change in load reduction behavior that was dependent on the excitation frequency and the contact condition. The load reduction exhibited in this study can be explained by a combination of stress superposition and friction reduction. It was found that a higher excitation frequency and a less complicated die-specimen interface were more likely to result in a friction reduction by high-frequency vibration.