Ultrathin, Ultralight “Nanocardboard” Recovers Shape After Bending

When choosing materials to make something, tradeoffs need to be made among properties such as thickness, stiffness, and weight. A new material called nanocardboard was developed that is made out of an aluminum oxide film with a thickness of tens of nanometers, forming a hollow plate with a height of tens of microns. Its sandwich structure, similar to that of corrugated cardboard, makes it more than 10,000 times as stiff as a solid plate of the same mass.