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A Novel Method for In Situ Electromechanical Characterization of Nanoscale Specimens
Published on: June 2, 2017
Deformación reversible inducida por la carga en un metal.
J Weissmüller1, R N Viswanath, D Kramer
1Forschungszentrum Karlsruhe, Institut für Nanotechnologie, Karlsruhe, Germany. Joerg.Weissmueller@int.fzk.de
Science (New York, N.Y.)
|April 12, 2003
Resumen
Los investigadores indujeron una tensión significativa y reversible en los metales utilizando poros nanoestructurados y voltaje aplicado. Este efecto electromecánico del metal rivaliza con la piezocerámica comercial, abriendo nuevas posibilidades para los actuadores metálicos.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La electroquímica es electroquímica.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los cambios de dimensión inducidos por el voltaje (por ejemplo, la piezoelectricidad) son comunes en la cerámica, los polímeros y las nanoestructuras de carbono.
- Tales efectos no se han observado previamente en metales.
- Los materiales existentes a menudo requieren una fabricación compleja o tienen limitaciones en la amplitud de deformación.
Objetivo del estudio:
- Para demostrar la deformación reversible inducida por el voltaje en los metales.
- Para lograr amplitudes de deformación comparables a las piezocerámicas comerciales en materiales metálicos.
- Explorar el mecanismo de los efectos electromecánicos en los metales nanoestructurados.
Principales métodos:
- Fabricación de metales con una red continua de poros de tamaño nanométrico.
- Impregnación de la red porosa con un electrolito.
- Aplicación de un potencial eléctrico relativo al electrolito para controlar la densidad de carga superficial.
Principales resultados:
- Amplitudes de deformación reversibles alcanzadas en metales comparables a las piezocerámicas comerciales (del orden del 0,1% o más).
- Se demostró que la estructura de los poros y la densidad de carga superficial son factores clave para inducir el efecto electromecánico.
- Estableció un nuevo método para generar una tensión significativa en sistemas metálicos.
Conclusiones:
- Los metales pueden exhibir una tensión reversible inducida por tensión significativa cuando se diseñan con nanoestructuras específicas y control de carga superficial.
- Este hallazgo desafía las suposiciones anteriores sobre la ausencia de tales efectos en los metales.
- El enfoque desarrollado ofrece una nueva vía para crear actuadores y sensores a base de metal.
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