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Propagación de ondas solitarias a lo largo de un frente de grieta en rápido movimiento
E Sharon1, G Cohen, J Fineberg
1The Racah Institute of Physics, The Hebrew University of Jerusalem, Givat Ram, Israel.
Nature
|March 10, 2001
Resumen
Recién descubierto recientemente descubierto.
Área de la Ciencia:
- Mecánica de las fracturas mecánicas.
- Ciencia de los materiales ciencia de los materiales.
- La mecánica de los sólidos.
Sus antecedentes:
- Las grietas en materiales frágiles a menudo se simplifican como objetos 1D en materiales 2D.
- Los materiales 3D reales exhiben superficies de grietas planas con frentes singulares.
- No se comprenden la dinámica y la morfología de los frentes de grietas que interactúan con las inhomogeneidades.
Objetivo del estudio:
- Investigar la dinámica de los frentes de grietas en materiales frágiles en 3D.
- Comprender el papel de las inhomogeneidades materiales en el comportamiento del frente del crack.
- Explicar la formación de la morfología de la superficie de la fractura.
Principales métodos:
- Simulaciones de la dinámica del frente de grietas en materiales frágiles en 3D.
- Análisis de la propagación de ondas a lo largo de los frentes de grietas.
- Examen de la interacción del frente de grietas con las asperidades.
Principales resultados:
- Las perturbaciones crean ondas localizadas de larga duración ("ondas frontales") que se propagan a lo largo de los frentes de grietas.
- Las ondas frontales se propagan aproximadamente a la velocidad de onda de Rayleigh.
- Las ondas frontales de contrapropagación mantienen la forma y la amplitud, creando huellas superficiales.
Conclusiones:
- Las ondas frontales son intrínsecamente fenómenos 3D, ausentes en las teorías de fractura 2D.
- Las ondas frontales proporcionan grietas con inercia y disipación.
- Pueden explicar la coherencia de grietas durante las interacciones con asperidades.
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