CAREER: Advancing ceramic processing science through acoustic characterization

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.