You don’t usually think about fruit when discussing metals or manufacturing. However, German scientists have found a way to bring the two together in conversation. Their new innovation has produced possibly the most advanced aluminum-based alloy we’ve ever seen, and the inspiration comes from the peel of a simple piece of fruit — specifically, the pomelo, which is an Asian grapefruit. From Popular Mechanics:
Materials scientists in Germany figured out how to build the same type of structure of aluminum. They say their new fruit-inspired composite has the best attributes of pure aluminum and an aluminum-silicon alloy, yielding a hybrid that resists deformation and is tough to break. Their work appears this week in the Journal of Materials Science.
Many man-made composite materials sacrifice one mechanical property for the sake of another. Either they’re tough, absorbing plenty of energy without rupturing, or they’re strong, withstanding greater force without yielding. Ceramic, for example, is strong but not very tough—it doesn’t bend, but it breaks. Some natural structures, however, such as bone, wood, and sea sponge needles, nicely combine both attributes.
Pomelos do this, too, but their peels are not as well understood. So researchers from the RWTH Aachen University and the University of Freiburg sliced open some store-bought fruit, sputtered their peels with gold and studied them under a scanning electron microscope. They saw that the cells were laid out in a hierarchical structure, comprising a foamy matrix of struts that shields the juicy fruit within. With their fluid-filled interiors and sturdy walls, the cells essentially act as pneumatic structures, with a ductile center surrounded by a strong outer shell.
Fruit-inspired metals may be the wave of the future when it comes to manufacturing. However, there’s still one trick that remains to be seen. This new alloy may be inspired by fruit, but is it also edible? We’re guessing this one’s a long, long way off.