| abstract |
The present invention relates to how to engineer the reversible elasticity of films and/or layers and/or substrates by using repeating Y-shaped patterns that are cut through the films and/or layers and/or substrates. For example, according to embodiments of the present invention, macroscopic dog-bone-shaped structures with a range of Y-shaped geometric parameters were fabricated using a 75 μm thick polyimide (PI) foil. The tensile strain response of the film at its breaking point was then recorded. The structure was also confirmed using finite element modeling. Once stretched, the PI strips deflect locally out of plane, allowing the foil to stretch macroscopically. |