What structural features arrest cracks in stony corals? A high-energy in situ microindentation-microtomography study

Non-metallic, inorganic large brittle structures are not usually interesting for their (rather poor) mechanical properties, however in nature, corals create large mineral structures that are impressively resilient against cyclic wave and tide forces. But how do coral features: struts, polyps, density and phase achieve this? We propose an in situ study in OD19 combining mechanical microindentation with high-energy radiography and tomography, to reveal interactions between indenter, microstructure and cracks, to reveal how the structure resists damage propagation. We will reveal how corals resist cracking and we will explore the interplay between porosity, shape and variable density domains in the struts and corralites. With this we hope to reveal motifs and principles of crack stopping, inspired by the coral system.