GOALI: Metal alloy powders via co-solvent assisted spray pyrolysis

CBET-0755703，Ehrman项目总结：本计画的目的是开发一种喷雾热解法，以廉价的金属盐为原料，生产金属合金微粒。来自杜邦公司和马里兰州大学的教师和工业研究人员将进行实验和模拟研究，以全面了解工艺条件和知识产权优点：喷雾热解方法提供了许多优于用于粉末生产的溶液相路线的优点，但是在工业规模上对金属的扩展仅限于少数抗氧化体系，例如银和钯。 添加高浓度还原气体以生产金属颗粒的要求限制了贱金属生产的扩展。在我们的方法中，助溶剂在反应器中分解产生少量氢气，低于空气中的可燃性极限，将金属盐晶体还原为金属粉末。该过程受动力学和热力学约束。分解过程的化学动力学建模将用于预测氢气的析出，而热化学建模将用于确定作为氧浓度和温度的函数的平衡相关系，以及基于质量和能量平衡的过程模型，以及基于统计的质量控制概念来指导过程设计。通过该项目，该团队将把工艺从实验室规模的单组分概念验证阶段推进到多组分合金粉末形成阶段，包括工艺放大和应用测试。更广泛的影响：目标应用是用于微电路材料生产的厚膜导电浆料，例如混合集成电路，嵌入式无源器件，以实现组件的收缩和多层陶瓷电容器的金属化。包含微电路材料的最终产品无处不在，从手机到太阳能电池再到汽车。更优质的材料将改善通信和安全，提高能源效率，以及影响生活质量的其他改善。基于气溶胶的生产路线是快速的并且通常是单步的，并且生产无溶剂和配体的产品粉末，也为促进制造业的可持续性提供了一般机会。除了电子材料之外，金属粉末还用于牙科和医疗植入物应用以及医疗设备，例如糖尿病患者的葡萄糖监测器，因此这项研究的结果也可能影响这些行业。拟议的产学合作所增加的价值包括：（1）将反应工程、气溶胶技术和材料科学的基本原理与工业过程开发和规模扩大活动相融合，以及（2）工业和大学研究人员与学生之间的互动，将允许从实验室创新到应用测试和研究扩展的所有阶段的参与，以提供信息从真实的世界角度开展教学和外联活动。

CBET-0755703, EhrmanProject Summary: The objective of this project is to develop a spray pyrolysis process for the production of metal alloy microparticles from inexpensive metal salt precursors.A team consisting of student, faculty and industrial researchers from DuPont and theUniversity of Maryland will conduct experimental and simulation based studies in order to develop a comprehensive understanding of relationship between process conditions and product characteristics.Intellectual Merit: Spray pyrolysis processes offer many advantages over solution phase routes for powder production, but extension to metals on an industrial scale has been restricted to only a few oxidation resistant systems such as silver and palladium. The requirement of addition of high concentrations of reducing gas to produce metallic particles has limited extension to base metal production. In our approach, the cosolvent decomposes in the reactor to produce small amounts of hydrogen, less than the flammability limit in air, reducing metal salt crystals to metallic powders. The process is governed by both kinetic and thermodynamic constraints. Chemical kinetic modeling of the decomposition process will be used to predict hydrogen evolution while thermochemical modeling to determine equilibrium phase relationships as a function of oxygen concentration and temperature will be used, together with a mass and energy balance based process model, and statistical based quality control concepts to guide process design. With this project, the team will take the process from bench scale single component proof of concept stage to multicomponent alloy powder formation, including process scale up and applications testing.Broader Impact: The target application is thick film conductive pastes used in the production of microcircuit materials, for example in hybrid integrated circuitry, embedded passives to enable shrinkage of components and metallization of multilayer ceramic capacitors. End products containing microcircuit materials are ubiquitous, ranging from cell phones to solar cells to automobiles. Better quality materials will lead to improved communications and safety, greater energy efficiency, and other improvements affecting quality of life. Aerosol-based production routes, which are rapid and often single step, and which produce solvent and ligand free product powders, also present a general opportunity for promotion of sustainability in manufacturing. Beyond electronic materials, metal powders are of interest for dental and medical implant applications as well as medical devices such as in glucose monitors for diabetics, and thus results from this research may impact these industries as well. Elements of the value added by the proposed industry-university collaboration include: (1) fusion of fundamental principles of reaction engineering, aerosol technology and materials science with industrial process development and scale up activities, and (2) interactions between industry and university researchers and students that will allow participation at all stages from laboratory innovation to applications testing and extension of the research to inform teaching and outreach activities with a real world perspective.