CAREER: Meso and Macro Hydroforming of Complex Shapes - Mechanics and Control

该学院早期职业发展（CAREER）研究的总体目标是了解不同尺度水平（中尺度和宏观）管状部件液压成形的基本力学，并建立基础知识，以制造复杂的宏观和微型（中尺度）管状部件。在管液压成形中，管状预成型件被放置在两个模具半体之间，管状预成型件由流体内部加压，同时管端部被朝向模具腔的中心轴向地进给或推动。实现这些目标的方法将通过分析建模、数值模拟和实验来研究与流体压力加载和材料进给有关的特性。由于变形过程中管材表面的演变和材料的可成形性对工艺的成功至关重要，因此将研究非常规加载路径，即，材料的分步进料、振动压力加载条件和双压力加载。将开发优化细观和宏观液压成形工艺的方案，以便除了获得良好的液压成形部件外，还增强摩擦学条件。从这项研究中建立的基本原理，预计将开辟新的途径，液压成形的复杂薄空心型材，超薄型材，和微型零件在汽车和电子行业的潜在影响。这些知识对于有兴趣在目前尚不存在的中尺度水平上开发有效的液压成形机系统的美国公司也将具有重要价值，并将为中空结构的新系统设计提供机会。研究结果将纳入大学课程，并通过研讨会、会议和期刊文章传播。该项目的主要目标之一是促进国际一级的机构间研究和教育合作。因此，将推出与日本和丹麦两所大学有联系的部分机构间制造课程。期望本课程能提供增进知识的机会，并为学生在全球经济下承担跨国公司的责任做好准备。

The overall objective of this Faculty Early Career Development (CAREER) research is to understand the fundamental mechanics of hydroforming of tubular components at different scale levels (meso and macro) and establish fundamentals to enable manufacturing of complex macro and miniature (meso-scale) tubular components. In tube hydroforming a tubular preform is placed between two die halves, the tubular preform is internally pressurized by fluid while the tube ends are fed or pushed axially towards the center of the die cavity. The approach to achieve the objectives will be studying the characteristics pertaining to fluid-pressure loading and feeding of material through analytical modeling, numerical, and experimentation. As the evolution of tubular surface during deformation and material formability are critical to the success of the process, non-conventional loading paths will be investigated, i.e., step-wise feeding of material, vibration pressure loading conditions, and dual pressure loading. Schemes for optimizing both meso and macro hydroforming processes will be developed such that in addition to obtaining a sound hydroformed part, the tribological conditions are enhanced. The fundamentals established from this study are expected to open new avenues for hydroforming of complex thin hollow sections, ultra-thin sections, and miniature parts with potential impact in automotive and electronic industries. The knowledge will also be of significant value to U.S. companies interested in developing effective hydroforming machine systems at a meso scale level which are non-existent at present, and will raise opportunities for new system designs of hollow structures. Research findings will be incorporated into university courses and dissemination through seminars, conferences, and journal articles. One of the main goals of this project is to promote interinstitutional research and educational collaboration at the international level. Thus, a partial interinstitutional manufacturing course linked to two universities from Japan and Denmark will be introduced. It is expected that this course will provide opportunities for knowledge enhancement and prepare students to assume responsibilities in multinational corporations under the global economy.