Precise Dynamic Control of the Mechanical and Self‐Healing Properties of an Electrolytic Cell with Soluble Porous Anode

Engineering products are currently designed to operate under a fixed set of conditions, but the demands of a dynamic environment may occasionally exceed these specifications, resulting in technical failures. Materials with properties that can be modulated in real time allow the functionality of a product to be dynamically tuned to meet these changing requirements. Having a single versatile product that meets multiple needs also eliminates the necessity for multiple parts with dedicated functionalities, conserving space, material, and energy. Here, a material with electrically tunable mechanical properties is demonstrated using an electrolytic cell with porous copper foams for electrodes. By controlling the voltage polarity, current density, and process duration, copper metal is reversibly deposited or etched from the foam in a precise and deterministic manner without changing its nominal volume or temperature. The resultant change in relative density, in turn, alters the modulus, strength, and energy absorption characteristics of the foams over a range of two orders of magnitude. By excessively depositing material at the interface of separate foam pieces, the system is shown to possess self‐healing characteristics as well. Finally, a demonstration of real‐time mechanical property modulation in a product prototype is carried out.