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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Magnetización residual químico-viscosa en el sistema Fe3O4-yFe2O3
Science (New York, N.Y.)
|February 24, 1989
Resumen
La magnetita de dominio único es una magnetita de dominio único.
Área de la Ciencia:
- La geofísica es la geofísica.
- Física mineral Física de los minerales
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- La oxidación de la magnetita (Fe3O4) a la magemita (gamma-Fe2O3) es crucial para los registros paleomagnéticos.
- La comprensión de la magnetización remanente en estos minerales informa la historia del campo magnético de la Tierra.
Objetivo del estudio:
- Investigar la magnetización remanente química (CRM) de la magnetita durante la oxidación a la magemita.
- Caracterice las propiedades de la magnetización de remanente químico-viscoso (CVRM) resultante.
Principales métodos:
- Oxidación de magnetita de dominio único a magemita a varias temperaturas (100-650°C) en un campo de 50 microteslas.
- Medición y comparación de la intensidad y resistencia a la desmagnetización del CRM y la magnetización de remanentes viscosos (VRM).
Principales resultados:
- La intensidad del CRM es similar a la del VRM en magnetita no oxidada bajo condiciones idénticas.
- Los restos muestran una resistencia comparable a la desmagnetización.
- La intensidad de CVRM exhibe un pico de tipo Hopkinson cerca del punto de Curie.
- El CVRM de alta temperatura es más resistente a la desmagnetización que la magnetización termoremanente (TRM).
Conclusiones:
- El remanente de magnetita oxidada es un CVRM, mezclando las características de CRM y VRM.
- CVRM está influenciado tanto por el núcleo de magnetita VRM y magemita superficie CRM a bajas temperaturas.
- Los procesos de oxidación tienen un impacto significativo en las propiedades de la remanencia magnética.
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