Scientists Introduce a Metal With Switchable Strength
Metallic material that switches between hard and soft states, by the Technical University of Hamburg.
When researchers experiment with smart materials that change properties with the introduction of an electrical current, these materials typically assume the form of thin wires or connectors attached to other materials. However, scientists Jörg Weißmüller and Hai-Jun Jin have recently produced a smart metal that may be used in a bulk application. When an electric charge is produced, the metal transforms between a strong and inflexible state to a soft and pliable state.
In order to create the material, the researchers dipped precious metals such as gold or platinum in an acidic bath. The acid corroded the metals enough to form pits, which were then filled with a conductive liquid. The interaction between electricity and the liquid caused the modified material to transform up to 200 percent in strength and ductility.
“For the first time we have succeeded in producing a material which, while in service, can switch back and forth between a state of strong and brittle behavior and one of soft and malleable,” Weißmüller said. “We are still at the fundamental research stage but our discovery may bring significant progress in the development of so-called smart materials.”