Ultrasonic Assisted Microextrusion and Microtube Hydroforming

该奖项的研究目标是研究超声辅助微成形的力学，重点是微挤压和微管液压成形。微成形是一种极具潜力的小型化技术，具有很高的生产效率。由于零件复杂、材料可成形性低、不均匀性、严重的摩擦学条件和其他尺寸效应而无法进行微成形的微型零件，超声辅助微成形具有很大的潜力。在本研究中，超声波振动对材料流动特性、材料成形性和摩擦学条件的影响将通过分析模型、数值和实验来研究。建立由超声振动和塑性变形引起的温度产生的分析模型。通过实验，研究不同能级超声振动引起的温升对材料特性的影响。研究超声能量对工具-工件界面润滑剂化学物质反应响应的影响，最终目的是为该工艺确定合适和有效的润滑剂化学物质。如果成功，从本研究中建立的基础将用于建立一个知识库，用于通过超声波辅助微成形开发具有成本效益的3d微型零件制造方法。从这项研究中获得的知识可能会导致新的热微成形工艺技术，其中钢坯加热是通过超声波振动引起的热能来实现的。该研究对微型零件制造商和大规模生产空心和固体微型零件的微成形机系统的开发人员具有重要的价值。微型零件需求量大的生物医学、电子、军械、通信等行业有望从中受益。研究结果将纳入制造课程，并通过研讨会、会议和期刊文章进行传播。研究生和本科生将受益于课堂教学和参与研究。

The research objective of this award is to study the mechanics of ultrasonic assisted microforming, focusing on micro-extrusions and microtube hydroforming. Microforming is one of the miniaturization technologies with great potential for high production rates. There is great potential for miniature parts that cannot be microformed due to part complexity, low material formability, inhomogenuity, severe tribological conditions and other size effects, to be successfully produced by ultrasonic assisted microforming. In this research, the influence of ultrasonic vibrations on material flow characteristics, material formability, and tribological conditions will be studied through analytical modeling, numerical, and experimentation. Analytical models for predicting temperature generation caused by ultrasonic vibrations, coupled with temperature induced due to plastic deformation will be established. Through experimentation, the transformation of material characteristics due to temperature rise caused by ultrasonic vibrations at different energy levels will be studied. The effect of ultrasonic energy on the reaction response of lubricant chemicals at the tool-workpiece interface will also be studied with an ultimate goal of identifying suitable and effective lubricant chemicals for this process. If successful, the fundamentals established from this study will be used to build a knowledge-base for developing cost-effective manufacturing method for 3D-miniature parts via ultrasonic assisted microforming. The knowledge gained from this research may lead to novel warm microforming process techniques, where billet heating is achieved through the heat energy induced from ultrasonic vibrations. This research will be of significant value to manufacturers of miniature parts and developers of microforming machine systems for mass production of hollow and solid micro parts. Biomedical, electronics, ordnance, and communication industries are expected to benefit from this technology due to high demand of miniature parts. Research findings will be incorporated into manufacturing courses and dissemination through seminars, conferences and journal articles. Graduate and undergraduate engineering students will benefit through classroom instruction and involvement in the research.