Collaborative Proposal: Manufacturing of Nanocrystalline Bulk Materials by Field Activated Sintering

将建立纳米颗粒材料现场处理的科学框架。 特别是，将开展详细的理论实验计划，其具体目标是：（a）评估和澄清纳米粉末的材料特性、微观结构几何形状和加工参数的相互依赖性，（b）量化通过烧结纳米粉末压块的电流传导并将其与制造和性能联系起来，以及（c）开发适用于大型和净形状零件的纳米晶材料的工艺设计/表征方法。该项目将：（a）产生基础知识尺寸尺度在现场加工中的作用，（b）阐明负责增强现场烧结性能的具体机制，（c）为工艺设计和优化该过程提供合理的基础，（d）在优化当前应用以及模具设计方面为复杂形状加工设计的新模型的开发提供指导。 此外，我们还将生成相当大的纳米晶材料样本，对结构、缺陷和机械性能进行广泛表征。晶粒尺寸小于100 nm的结构材料具有异常高的强度、硬度和耐磨性，以及良好的抗疲劳性。 该项目重点关注通过场辅助烧结生产的块状纳米晶材料的制造和表征，该材料可以从纳米尺寸粉末开始生产近净形状的块状部件，并在加工过程中保留微观结构的规模。开发用于制造散装纳米级材料的科学加工基地将是这种令人兴奋的新型材料商业化的重要一步，这种材料保留了纳米晶粒尺寸并结合了不寻常的特性。两所大学之间的这一合作提案将产生协同效应，以增强德雷塞尔大学进行的建模和加州大学戴维斯分校通过实验对纳米工艺的理解。研究计划中的教育和培训的整合将通过为德雷塞尔大学和都柏林大学的学生开发“散装纳米材料的制造”研讨会课程来实现。我们将继续通过 REU 补充品让本科生参与研究。

A scientific framework will be established for field processing of nanosize particulate materials. In particular, a detailed theoretical-experimental program will be pursued with specific goals to: (a) evaluate and clarify the interdependence of material properties, geometry of microstructure and processing parameters of nanosize powders, (b) quantify the conduction of electric current through sintering nanopowder compacts and relate them to manufacturing and properties, and (c) develop a process design/characterization methodology for this technology that is applicable to nanocrystalline materials for large and net shape parts.This project will: (a) generate fundamental knowledge of the role of size scale in field processing, (b) elucidate specific mechanisms responsible for the enhanced performance of field sintering, (c) provide a rational basis for process design and optimization of this process, (d) provide guidance for the development of new models for design of complex shape processing in terms of optimization of current application, as well as die design. In addition, we will generate sizable specimens of nanocrystalline materials that will be extensively characterized for structure, defects and mechanical properties.Structural materials with grain size less than 100 nm are characterized by unusually high strength, hardness and wear resistance, as well as good fatigue resistance. This project focuses on the manufacturing and characterization of bulk nanocrystalline materials produced by field assisted sintering that can produce near net-shape bulk components starting from nanosize powders, and retains the scale of the microstructure during processing. The development of a scientific processing base for manufacturing of bulk nanoscale materials will be a major step towards commercialization of this exciting new class of materials which preserve nanometric grain size and combine unusual properties. This collaborative proposal between two Universities will provide a synergistic effect to enhance both modeling performed at Drexel University and nano-process understanding by experiments at University of California Davis.The integration of education and training within the research program will be achieved by developing a seminar course for Drexel and UCD students on "Manufacturing of bulk nanomaterials". We will continue involving undergraduate students in research by REU supplements.