CAREER: Advancing ceramic processing science through acoustic characterization

这个职业奖项目通过冷烧结的工艺探索了致密多晶陶瓷材料的发展。传统的烧结方法涉及热和压力的结合，需要大量的时间和高温才能在最终的陶瓷产品中达到所需的密度、微观结构和性能。相比之下，冷烧结提供了一种更节能的替代方案，显著减少了加工时间，在5到60分钟之间，温度更低。因此，冷烧结可以为制造电陶瓷提供一种环保的替代方案，这可能成为跨行业开发新技术的一个日益相关的问题。然而，尽管实现了较高的相对密度，一些通过冷烧结生产的材料并没有表现出与通过传统烧结方法制造的材料相比的机械或功能特性。在美国国家科学基金会材料研究部陶瓷项目的支持下，首席研究员和她的研究小组研究了冷烧结材料的加工方法、微观结构结果和性能之间的联系。该项目涉及开发一个多方面的表征方法，强调声学测量技术，为这项调查。这项研究可能最终导致大规模生产的可行性，通过揭示潜在的机制，确保通过冷烧结制备均匀、高性能、功能的陶瓷组件。利用研究的跨学科性质，该项目为不同阶段的学生和专业人士提供有针对性的教育体验。计划开展的活动包括编写全面的教育材料和一个沉浸式暑期项目，旨在激发小学生，特别是年轻女孩和西班牙裔学生对声波传播的兴趣和理解。该职业奖由美国国家科学基金会材料研究部陶瓷项目支持，通过对制造过程的多模态和实时监控，促进了对加工条件对冷烧结部件最终结构的作用的基本理解。更具体地说，这个CAREER项目研究了使用声学方法来表征冷烧结试样中的微观和宏观缺陷，从而对影响陶瓷烧结过程的主要机制有了基本的了解。使用声学方法对有效性质和结构进行初步无损评估，有助于使用常规方法（包括x射线计算机断层扫描和电子显微镜）在更小的尺度上进行有针对性的表征。通过研究各种工艺参数对冷烧结零件的微观结构和性能的影响，该项目为实现包括陶瓷和有机-无机混合材料在内的大量材料系统的环保，节能生产提供了基本的理解。这一总体基础对于其他新型陶瓷加工方法和新开发的材料系统的表征至关重要。首席研究员和她的研究小组使用的方法也有助于改进现有的弹性波传播和散射模型，通过改进的有效介质模型和复杂的微观结构特征，结合压电耦合的影响，通过代表性的体积元方法。这些方法在无损材料表征领域取得了重大进展。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical AbstractThis CAREER award project explores the development of dense polycrystalline ceramic materials through a process known as cold sintering. Traditional sintering methods, which involve a combination of heat and pressure, require extensive time and high temperatures to achieve desired densities, microstructures, and properties in the final ceramic product. In contrast, cold sintering presents a more energy efficient alternative, significantly reducing processing times to between 5 to 60 minutes and lower temperatures. Thus, cold sintering can provide an eco-friendly alternative to manufacturing electroceramics, which is likely to become an increasingly relevant issue in developing new technologies across industries. However, despite achieving high relative densities, some materials produced via cold sintering do not exhibit mechanical or functional properties comparable with those created through conventional sintering methods. With this CAREER award, supported by the Ceramics program in NSF’s Division of Materials Research, the principal investigator and her research group investigate connections between the processing methods, microstructural outcomes, and properties of cold sintered materials. The project involves developing a multifaceted characterization approach, emphasizing acoustic measurement techniques, for this investigation. The research could eventually lead to large-scale manufacturing feasibility by uncovering the underlying mechanisms that ensure uniform, high-performing, functional ceramics components prepared by cold sintering. Leveraging the interdisciplinary nature of the research, the project provides targeted educational experiences for students and professionals at various stages. Activities planned include development of comprehensive educational materials and an immersive summer program designed to spark interest and understanding in sound and wave propagation among elementary school students, particularly young girls and students of Hispanic heritage.Technical AbstractThis CAREER award, supported by the Ceramics program in NSF’s Division of Materials Research, advances the fundamental understanding of the role processing conditions play regarding the resulting structure of cold sintered components using multi-modal and real-time monitoring of the manufacturing process. More specifically, this CAREER project examines the use of acoustic methods to characterize micro- and macro-flaws in cold sintered specimens, yielding a fundamental understanding of the primary mechanisms impacting the ceramic sintering process. The initial nondestructive assessment of effective properties and structures using acoustic methods facilitates targeted characterization at significantly smaller scales using conventional methods including X-ray computed tomography and electron microscopy. By studying the influence of various processing parameters on the resulting microstructure and properties of cold sintered parts, this project provides the fundamental understanding to enable eco-friendly, energy-efficient production of a large suite of material systems, including ceramics and organic-inorganic hybrid materials. This general foundation is critical in the characterization of other novel ceramic processing approaches and newly developed material systems. The methods the principal investigator and her research group use also help advance existing models of elastic wave propagation and scattering by incorporating the effects of piezoelectric coupling through modified effective medium models and complex microstructural features through representative volume element approaches. These methods provide a significant advancement in the field of nondestructive material characterization.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.