Use of magnetic resonance to investigate magnetic fluids for transformers application

作者：Leite E S^*; Silva O; Skeff Neto K; Sartoratto P P C; Viali W R; Morais P C

来源：Revista Mexicana de Fisica, 2012, 58(2): 249-252.

• Transformer
• magnetic fluid
• magnetic resonance
• nanoparticle

Magnetic resonance (MR) was used to investigate two magnetic fluid (MF) samples containing nanosized (average 3 nm in diameter) iron oxide particles suspended in insulating mineral and vegetal oils. The MR spectra were analyzed using two Lorentzian-like components. Analysis of the temperature (T) dependence of the resonance field (H-R) indicates that the lower-field (higher-field) resonance line accounts for monomers (chain-like units). The solid-liquid phase transition of the MF samples, taking place around the melting point of the insulating oil (solvent), is indicated by a cusp in the H-R x T curve, which is more pronounced for the lower-field resonance line component. This finding was associated to a higher reorientation of the monomer%26apos;s magnetic moment upon melting of the MF sample.

• 出版日期2012-12