MicroCoral: Unlocking the micromechanical properties of cold-water coral skeletons

• Applicant: Professor Dr. Uwe Wolfram
• Subject Area: Polymeric and Biogenic Materials and Derived Composites ; Biomaterials
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 547950715

We here aim at exploring the building material of cold-water coral skeletons. Cold-water corals are among the most abundant in the world, creating marine habitats and ecosystems that are crucial biodiversity hubs. The reefs they make are often considered as “rain forests” of the deep but these reefs are threatened by climate change and ocean acidification. While this is also true for tropical corals, the threats cold-water corals face are distinct and more significant and could lead to a dramatic and rapid habitat loss. This is certainly daunting and a major challenge but there is something about cold-water corals that is fascinating – at least for us as materials scientists. Cold-water coral reefs are found around the globe in depths between 50 m and 4,000 m where there is no sunlight, the environment is chilled to between 4°C and 12°C, and energy as well as other resources are scarce. Together with their tropical relatives, cold-water corals nevertheless build the largest bioconstruction in the world. Our preliminary results show that they do so by using a building material that is 10 times stronger than concrete. Our results furthermore suggest that they are able to achieve their remarkable material properties even under climate change impacts, which we showed in samples from a region that is considered to be representative of a climate change impacted end-of-century ocean. This triggers fundamental questions: (i) What makes their building material so strong? (ii) How can they achieve this strength despite climate change? (iii) How can we unlock and provide these concepts to enable the engineering of sustainable and multifunctional equivalents? To answer these questions, we here want to (i) investigate the structural and compositional properties of cold-water coral skeletons, (ii) explore their mechanical properties from crystal lattice to macroscopic length-scales, (iii) model the non-linear material behaviour across these length scales, and (iv) create a digital material representation to enable the application of the mechanisms behind their impressive mechanical properties in materials engineering. To do so, we will build on experimental and computational methods we have developed and implemented over the past years. Unlocking and providing their materials concepts digitally is highly interesting since cold-water corals efficiently produce a calcified material with exceptional properties in extreme environments and with limited resources. The timely results of our project could have the potential to enable transformative materials, fostering innovation across several engineering sectors and addressing global needs with a focus on biocompatibility, multifunctionality, and sustainability.

• DFG Programme: Research Grants