National Institute of Standards and Technology (NIST) Advanced Manufacturing Technology Consortia (AMTech) Program Award Number: 70NANB14H056 Development of Roadmap and Consortium for Innovation in Sheet Metal Forming Challenge Code Group 3 3.1 Ultrasonic-Assisted Forming for Process Enhancement

3.1 Ultrasonic-Assisted Forming for Process Enhancement Objective: Improving metal forming processes through the application of ultrasonic vibration System Requirements Technical Benefits: Reduced forming force Reduced interface friction Reduced tool wear Better surface finish Potential for matl. softening Difficult-to-form geometry/ material may be feasible Widen process window (e.g. higher LDR ) Acquire resonance under loading condition Minimize the energy losses. Maximize the effects of ultrasonic oscillations Offer stability Ultrasonic metal forming setup UNH - 28 October 2016 Sheet Metal Forming

3.1 Ultrasonic-Assisted Forming for Process Enhancement Technical and Non-Technical Challenges : Research on ultrasonic forming has been carried out for decades, yet there is no widespread application of the technology in industry! Fundamental understanding of ultrasonic forming process: Effects of vibration frequency, mode, and amplitude on flow stress, microstructure and friction. Tooling and system design (to acquire resonance frequencies) Strategies to minimize ultrasonic energy input (process viability) Candidate processes that will yield economic benefits (micro/meso/macro scale proc., forming load patterns, ) Availability of high power ultrasonic generators for industrial usage Tooling design requires reliable numerical modeling: Modal analysis and frequency response analysis (damping ratios which are function of mating surfaces are difficult to determine ) Challenges to address UNH - 28 October 2016 Sheet Metal Forming

3.1 Ultrasonic-Assisted Forming for Process Enhancement Path to Implementation: Carry out ultrasonic experiments using a basic test set up such as plane strain sheet drawing and study the influence of ultrasound variables on friction force, microstructure, etc. With the aid numerical modeling develop tooling design guidelines for ultrasonic assisted sheet forming. This will include classification of sheet forming processes that are ideal and cost effective for ultrasound technology. Optimize ultrasonic energy usage by developing innovative methods for selectively applying ultrasonic vibrations in critical areas, particularly for large tooling. In collaboration with manufactures of ultrasonic generators/systems, explore the potential for developing industrial scale ultrasonic systems with feedback module for tuning resonance frequency in real time. Based on the input from the Center members regarding geometry, processes, and materials of interest and the knowledge gained from the above tasks, design experimental setup for ultrasonic-assisted deep drawing and conduct experiment under different ultrasonic conditions and assess the performance (tribological enhancement, microstructural changes, part quality, and load reduction) . UNH - 28 October 2016 Sheet Metal Forming

3.1 Ultrasonic-Assisted Forming for Process Enhancement Discussion: Timing: priority, resources available when needed? Obstacles: technical & business? Resources: level, type & issues? Anything missing for active industry support? Estimated benefits realistic & complete? Technical and non-technical obstacles complete or over reaching? Alternative implementation paths or better approaches? Conflicts with intellectual property or trade secrets? UNH - 28 October 2016 Sheet Metal Forming

3.1 Ultrasonic-Assisted Forming for Process Enhancement Example: Design issues encountered in micro extrusion Variant mode shapes UNH - 28 October 2016 Sheet Metal Forming