GOALI: Engineering Coating Microstructure Through Advanced Plasma Spray Processing: Fuel Cell and Thermal Barrier Applications

这项研究的重点是开发增强的等离子喷涂处理能力，以满足两个重要领域的先进材料和制造要求：新兴的燃料电池工业和用于发动机和动力应用的先进热障涂层（TBC）。该研究旨在扩大科学基础，以更好地理解这些应用中关键的过程-结构-性能关系，并利用这些知识开发先进的实时控制系统，更直接地控制决定最终微观结构的过程物理。这样做的好处是扩大了设计先进涂层系统的能力，并提高了制造能力。我们的研究方法旨在弥合实验研究的广泛参数化设计与涉及高度“理想化”条件（如光滑界面上的单飞溅）的过程物理的更基本研究之间的差距。等离子喷涂是一种高通量、经济、低环境影响的工艺，可用于定制工程涂层微结构，以满足特定的性能要求。然而，燃料电池和先进的TBC应用对于提高能源效率和减少环境影响非常重要，需要能够设计涂层结构并满足制造要求（产量和变化水平），这超出了目前的等离子喷涂能力。我们关注这两种应用不仅是因为它们的重要性，还因为它们涉及相同的陶瓷材料（钇稳定氧化锆，YSZ），但微观结构要求明显不同。我们相信，通过将我们的开发工作建立在对过程结构关系的更深入的了解之上，我们将开发出一个可推广和广泛应用的控制系统。这项研究将由一个跨学科的学术和行业研究人员团队进行，他们在材料、热流体、控制、制造和应用领域具有专业知识。为了更好地理解真实加工条件下复杂的工艺结构问题，我们将采用建模与实验相结合的方法。研究领域包括：A)发展对决定关键涂层特征的工艺-结构关系的基本物理的更全面的理解；b)发展非量维化模型，将工艺物理和可测量的工艺特性与生产目标（如涂层厚度和沉积速率）联系起来；c)根据其对涂层结构和控制要求的影响调查工艺的分布性质。d)将这些元素明确地纳入高级控制系统的体系结构中。在我们的行业合作伙伴（目标合作伙伴：西门子-西屋和恩格尔哈德表面技术公司）的专业知识指导下，我们将评估这些新能力，以满足燃料电池和TBC的要求。基于我们过去9年的记录（38名本科生研究人员中有50%来自代表性不足的群体），我们打算继续积极地让代表性不足的群体和本科生参与我们的研究。

This research is focused on developing enhanced plasma spray processing capabilities that will enable meeting the advanced materials and manufacturing requirements in two important areas: the emerging fuel-cell industry and advanced thermal barrier coatings (TBC) for engine and power applications. The research is directed at both expanding the science base needed to better understand the process-structure-property relationships critical for these applications, as well as utilizing this knowledge to develop an advanced real-time control system that more directly controls the process physics that determines the resulting microstructure. The benefit will be both in expanding the ability to engineer advanced coating systems as well as improving manufacturing capabilities. Our research approach is designed to bridge the gap between extensive parametric design of experiments studies and more fundamental studies of the process physics involving highly "idealized" conditions, such as single splats on smooth interfaces. Plasma spray is a high-throughput, economical, low environmental impact process that can be used to custom engineer coating microstructure to meet specific performance requirements. However, fuel-cell and advanced TBC applications, important to improving energy efficiency and reducing environmental impact, require the ability to engineer coating structure and meet manufacturing requirements (yield and variation levels) that are beyond today's current plasma spray capabilities. We focus on these two applications not only because of their importance, but because they involve the same ceramic material (yitria stablized zirconia, YSZ) but with significantly different microstructural requirements. We believe that by basing our development effort on a deeper knowledge of the process-structure relations, we will develop a control system that is generalizable and widely applicable. This research will be conducted by an interdisciplinary team of academic-industry researchers with expertise in materials, thermal-fluids, controls, manufacturing, and the application areas. We will take a combined modeling-experimental approach in order to better understand the complex process-structure issues under real processing conditions. Research areas include: a) developing a more complete understanding of the underlying physics that determines the process-structure relationships for critical coating features, b) developing non-dimensionalized models to relate the process physics and measurable process characteristics to production objectives such as coating thickness and deposition rate, c) investigating the distributed nature of the process in terms of its impact on coating structure and control requirements, and d) incorporating these elements explicitly into the architecture of an advanced control system. Guided by expertise from our industry co-PI's (GOALI Partners: Siemens-Westinghouse and Engelhard Surface Technologies), we will then evaluate these new capabilities in meeting the fuel-cell and TBC requirements. Building on our record over the past 9 years (50% of 38 undergraduate researchers were from underrepresented groups), we intend to continue actively involving underrepresented groups and undergraduate students in our research.