Credit: Wikimedia Commons


The search for natural wisdom often leads to surprising places. A team of scientists from the RWTH Aachen University Foundry Institute and University of Freiburg Plant Biomechanics Group sought to develop a more robust aluminum composite structure. For a model precedent, they turned to a pomelo fruit peel. The world's largest citrus fruit with a taste similar to grapefruit, the pomelo has a hierarchically-layered peel comprised of fiber-reinforced foam. This tough outer surface allows the 1-2 kg fruit to survive intact after 10 meter drops—a capacity that attracted the researchers' attention.

The scientists translated the microstructure of the pomelo skin into a metal composite with a robust alloy of aluminum-silicon on the outside and a pliable aluminum core. The resulting hybrid outperforms either of its parts, with a greater ductility than the aluminum-silicon alloy and a higher tensile strength than pure aluminum. Based on the experiment's success, the researchers aim to develop high-performance automotive components and other applications benefiting from lightweight and resilient materials.

Blaine Brownell, AIA, is a regularly featured columnist whose stories appear on this website each week. His views and conclusions are not necessarily those of ARCHITECT magazine nor of the American Institute of Architects.