CMMI-EPSRC: Damage Tolerant 3D Micro-Architectured Brittle Materials

The search for lightweight materials that can withstand extreme service conditions has been one of the major driving forces in material development in recent decades. Ceramic materials are often the preferred choice for such conditions due to their stability at high temperatures and in harsh environments. However, their inherent brittleness and low damage tolerance compared to metallic materials limit their structural applications. An emerging class of materials known as micro-architectured materials holds great potential for overcoming these limitations. Therefore, the overarching goal of this US-UK collaborative project is to develop a deeper understanding of fracture and damage tolerance in a wide variety of micro-architectured materials made from purely brittle parent materials which are ceramic/ceramic-like. These materials not only have potential structural applications but are also sought after for other contemporary technologies such as energy, biomedical devices, and micromechanical devices. This project will facilitate damage tolerance and structural integrity analysis for the reliable use of micro-architectured materials in these technologies. The project’s education and outreach plans are also closely integrated with the research plan, with a shared focus on the mechanics of micro-architectured materials. This includes developing interactive and open-access instructional materials on the subject, providing training to graduate students and postdoctoral researchers, and increasing awareness of mechanics and micro-architectured materials through museum exhibits aimed at K-12 students. Furthermore, this bi-national collaborative project will contribute to the development of a diverse and globally engaged technical workforce in both experimental and computational mechanics and materials science. The specific objectives of this project are twofold. Firstly, to determine the mechanisms of crack growth and damage tolerance in large-scale 3D periodic micro-architectures composed of linear elastic brittle parent materials. Secondly, to extend the understanding of fracture mechanisms to stochastic micro-architectures made of brittle ceramic parent materials. This project will go beyond the traditional understanding of classical fracture mechanics and associated testing protocols by developing a comprehensive understanding of damage tolerance and devising a novel methodology to characterize the fracture response of a wide variety of 3D micro-architectured materials made from purely brittle materials. Furthermore, by achieving these objectives, the project aims to test hypotheses, address fundamental questions with technological relevance, and develop structure-property-performance maps that will facilitate goal-oriented design and selection of optimal micro-architectures. This research is a collaborative effort under the NSF Directorate for Engineering - UKRI Engineering and Physical Sciences Research Council Lead Agency Opportunity (ENG-EPSRC), NSF 20-510. 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.