A Transatlantic Institute for Volumetric Powder Bed Fusion

跨大西洋体积粉末床融合研究所

• 批准号: 1728015
• 负责人: Carolyn Seepersad
• 金额: $ 39.98万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1728015&HistoricalAwards=false
• 关键词: Transatlantic; Institute; Volumetric; Powder; Bed

Although the additive manufacturing (AM) industry is projected to grow at an increasing rate, one of the most significant barriers to additional growth is the slow build speed of most AM technologies. The transatlantic institute for volumetric powder bed fusion (PBF) is focused on removing that barrier. PBF is an AM technology that fabricates parts by selectively fusing powdered material with a heat source (typically, a laser) in a layer-by-layer process. It is one of the most widely used AM technologies for building functional end-use parts, but it can be quite slow, requiring hours or days to build a large part. The objective of this project is to build the research foundation for a volumetric PBF process that has the potential to increase production rates by more than an order-of-magnitude by sintering the parts volumetrically rather than layer-by-layer. This project is a collaboration between leading AM researchers at The University of Texas at Austin and the University of Nottingham, with matching funds pledged from the UK ESPRC, so it is expected to build a new framework for US-UK collaboration to overcome the limitations of current AM technologies. Opportunities for international student and faculty exchanges, virtual institutes, and undergraduate research projects will enhance the collaboration and provide opportunities for international networking and mentoring. This award is co-funded by the Office of International Science and Engineering. The research moves beyond the current layer-based approach to rapidly create 3D objects in a volumetric fashion. The research path for volumetric PBF is to deposit powdered material with a patterned dopant in a layer-wise fashion. The dopant will be engineered to selectively absorb microwave/RF energy. Once the layers are formed, the volume will be subjected to microwave/RF fields that sinter only where the dopant is present, eliminating the need for layer-by-layer heating and increasing build speeds. To realize this volumetric PBF capability, fundamental research tasks are planned to build our knowledge of how dopants affect selective heating of polymer powder beds induced by RF/microwave radiation. Computational and physical experiments will determine appropriate dopants and concentrations and processing conditions for maximizing part accuracy and mechanical properties and minimizing processing time. Physical experiments will also determine the best material jetting routes to deposit the dopants accurately and uniformly over the selective area and evaporate the solvent carriers quickly.

尽管增材制造（AM）行业预计将以越来越快的速度增长，但进一步增长的最重要障碍之一是大多数AM技术的构建速度缓慢。 跨大西洋粉末床聚变研究所（PBF）致力于消除这一障碍。 PBF是一种AM技术，通过在逐层工艺中选择性地用热源（通常是激光）熔融粉末材料来制造零件。 它是用于构建功能性最终用途部件的最广泛使用的AM技术之一，但它可能非常缓慢，需要数小时或数天才能构建大型部件。 该项目的目标是为体积PBF工艺建立研究基础，该工艺有可能通过体积烧结而不是逐层烧结零件来提高生产率。该项目是德克萨斯大学奥斯汀分校和诺丁汉大学的领先AM研究人员之间的合作，英国ESPRC承诺提供配套资金，因此预计将为美英合作建立新的框架，以克服当前AM技术的局限性。 国际学生和教师交流，虚拟学院和本科生研究项目的机会将加强合作，并为国际网络和指导提供机会。该奖项由国际科学与工程办公室共同资助。该研究超越了当前基于层的方法，以体积的方式快速创建3D对象。 体积PBF的研究路径是以逐层方式存款具有图案化掺杂剂的粉末材料。 掺杂剂将被设计成选择性地吸收微波/RF能量。 一旦层形成，体积将经受微波/RF场，仅在存在掺杂剂的地方烧结，从而消除逐层加热的需要并提高构建速度。 为了实现这种体积PBF的能力，基础研究任务计划建立我们的知识，掺杂剂如何影响选择性加热的聚合物粉末床引起的RF/微波辐射。计算和物理实验将确定适当的掺杂剂和浓度以及加工条件，以最大限度地提高零件精度和机械性能，并最大限度地减少加工时间。 物理实验还将确定最佳的材料喷射路线，以在选择区域上准确且均匀地存款掺杂剂，并快速蒸发溶剂载体。

项目成果

Volumetric fusion of graphite-doped nylon 12 powder with radio frequency radiation

• DOI: 10.1108/rpj-09-2020-0218
• 发表时间: 2021-09
• 期刊: Rapid Prototyping Journal
• 影响因子: 3.9
• 作者: J. Allison;J. Pearce;J. Beaman;C. Seepersad

Computational design strategy to improve RF heating uniformity

提高射频加热均匀性的计算设计策略

• DOI: 10.1108/rpj-08-2021-0193
• 发表时间: 2022
• 期刊: Rapid Prototyping Journal
• 影响因子: 3.9
• 作者: Allison, Jared;Pearce, John;Beaman, Joseph;Seepersad, Carolyn
• 通讯作者: Seepersad, Carolyn