Optimising fracture toughness through tailored multi-scale microstructure

High strength and toughness is traditionally an elusive combination of material properties, since high strength materials (eg. ceramics) possess low ductility. New engineering materials are taking inspiration from nature to achieve both high strength and high fracture toughness through hierarchical microstructural features which act to arrest, dissipate energy or deviate cracks. Promising examples are magnetically assisted slip casting (MASC) ceramics and freeze-cast aerogel composites, which possess bricks-and-mortar, and lamellar architectures respectively. Our aim is to establish quantitative links between microstructural features and restraint of crack propagation within these materials.