Material fractures present a major obstacle to safety and economic efficiency across a wide range of industries, including construction, manufacturing, transportation, and aerospace. This highlights the urgent need for new material systems that offer fracture resistance far beyond the capabilities of traditional materials. This award supports fundamental research to enable the design and creation of a new class of fracture-resistant mechanical metamaterials (MMs). These materials exhibit extraordinary mechanical properties due to their structural geometry rather than chemical composition. Despite their promise, how these MMs break and how to design them to resist fracture remain underexplored. This project will address this gap by developing a new, hierarchical approach to analyze and optimize fracture resistance in MMs across global and local scales. The research is expected to generate new insights and design principles for fracture-resistant MMs, reduce economic losses resulting from material failure, and enable the development of safer and more durable technologies. In addition, the project will contribute to national educational goals by developing interactive educational tools and training students in a multidisciplinary environment that spans mechanics, materials science, and computational design through university programs and courses. This project aims to develop a hierarchical framework for understanding and designing multi-scale MMs with enhanced fracture resist