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Interruptor orgánico cristalino rápidamente reversible para la conversión de calor en energía mecánica
Madushani Dharmarwardana, Srimanta Pakhira1, Raymond P Welch
1Discipline of Physics, Discipline of Metallurgy Engineering and Materials Science (MEMS) & Centre for Advanced Electronics (CAE), Indian Institute of Technology Indore (IIT Indore), Simrol, Khandwa Road, Indore 453552, Madhya Pradesh (M.P.), India.
Journal of the American Chemical Society
|April 6, 2021
Resumen
Los investigadores desarrollaron un actuador termomórfico reversible a partir de cristales orgánicos. Este material exhibe una contracción y expansión rápidas y repetibles con cambios de temperatura, lo que permite nuevas aplicaciones de fusibles térmicos.
Área de la Ciencia:
- Ciencias de los materiales
- La cristalografía
- Química Física
Sus antecedentes:
- El comportamiento termoelástico en estado sólido es poco común en los cristales orgánicos.
- Los sistemas reversibles existentes a menudo son lentos, limitados en ciclos o se degradan rápidamente.
Objetivo del estudio:
- Desarrollar un actuador termomórfico totalmente reversible con mayor estabilidad y activación rápida.
- Para demostrar un nuevo material para aplicaciones de conmutación térmica en tiempo real.
Principales métodos:
- Investigación del comportamiento termoelástico en estado sólido en cristales orgánicos.
- Caracterización de las transiciones de fase de los cristales y de las propiedades de activación bajo ciclos térmicos.
Principales resultados:
- Se creó un actuador termomórfico estable y reversible, funcional durante más de 200 ciclos.
- Los cristales se contraen instantáneamente a un 90% de longitud al calentarse (> 45 °C) y se expanden al enfriarse (< 35 °C).
- La transición de fase es rápida con una histeresis mínima, lo que permite un ciclo rápido.
Conclusiones:
- El actuador de cristal orgánico desarrollado ofrece una solución robusta y eficiente para aplicaciones termomórficas.
- Las propiedades del material son adecuadas para crear fusibles térmicos de activación rápida y en tiempo real.
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