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Un micro-rejilla monocristalina de doble escala y resistente a los daños en la estrella de mar protoreaster nodoso
Ting Yang1, Hongshun Chen1, Zian Jia1
1Department of Mechanical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
Science (New York, N.Y.)
|February 10, 2022
Resumen
Los científicos descubrieron una única micro-rejilla cristalina en el esqueleto de una estrella de mar. Esta estructura de doble escala mejora la tolerancia al daño, ofreciendo ideas para el diseño de materiales celulares avanzados.
Área de la Ciencia:
- Ciencias de los materiales
- La biomineralización
- Biología estructural
Sus antecedentes:
- Los sólidos celulares como espumas y panales son frecuentes en la naturaleza y la ingeniería debido a su eficiencia mecánica.
- Los materiales celulares existentes generalmente comprenden componentes policristalinos o amorfos.
Objetivo del estudio:
- Para reportar una inusual doble escala, una sola micro-red cristalina en el esqueleto biomineralizado de la estrella de mar, Protoreaster nodosus.
- Investigar las características estructurales y cristalográficas de esta micro rejilla biológica.
- Para proporcionar ideas para el diseño de sólidos celulares con arquitectura sintética.
Principales métodos:
- Análisis de la microestructura del esqueleto de la estrella de mar.
- Caracterización de la geometría de la micro rejilla y la alineación cristalográfica.
- Investigación del comportamiento de la fractura a nivel atómico y de celosía.
Principales resultados:
- Descubrimiento de una micro celosía monocristalina con una geometría de superficie mínima periódica en forma de diamante (aprox. Constante de celosía de 30 micrómetros).
- Alineación cristalográfica de la dirección [111] con el eje c de calcita a escala atómica.
- Observación de gradientes estructurales a nivel de celosía, dislocaciones y comportamiento de la fractura concoidal.
Conclusiones:
- La micro rejilla de doble escala, alineada cristalográficamente, mejora significativamente la tolerancia al daño.
- Este diseño biológico ofrece información valiosa para el desarrollo de nuevos sólidos celulares de arquitectura sintética.
- Las estructuras jerárquicas en materiales biomineralizados presentan principios de diseño avanzados para la ciencia de los materiales.
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