Observatorio de I+D+i UPM

Memorias de investigación
Research Publications in journals:
Polymer bonded anisotropic thick hard films for micromotors/microgenerators
Year:2007
Research Areas
  • Optics, electromagnetism,
  • Physics - Soft condensed matter,
  • Magnetic materials
Information
Abstract
Abstract: Hard magnetic films are very promising elements for the production of MEMS, due to the optimum scaling properties of magnetic interactions. These elements are specially well suited for the development of micromotors and microgenerators. A magnetization multipolar structure is required on the material to be used in such applications. In order to generate this multipolar structure, a well defined magnetic anisotropy is required, this anisotropy being directed in many cases in the direction perpendicular to the film plane. The maximum torque obtainable from a micromotor depends mainly on the mass of magnetic material (i.e. the film thickness). Anisotropic hard magnetic films with thicknesses on the order of tenths of millimetres can not be prepared by any of the common thin film deposition techniques available nowadays. Though some preparation techniques have been developed that can be used to prepare hard magnetic films with the desired thicknesses, they are not able to produce materials with a well defined anisotropy along the direction perpendicular to the film plane. In this work, we describe a method to prepare anisotropic hard magnetic films with thicknesses of tenths of millimetres by dispersing NdFeB anisotropic microparticles on a polymethyl methacrylate (PMMA) solution at room temperature under low intensity magnetic fields. Large macrospic anisotropies have been reached for magnetic fields as low as 150 Oe applied during the deposition, with room temperature coercivities in excess of 1.2 T and maximum energy products up to 9 MGOe. The analysis of the temperature dependence of the magnetic properties indicates that a columnar arrangement of the particles on the direction parallel to the field applied during the preparation is the reason of the observed macroscopic anisotropy. The films can be easily deposited onto different substrates and mechanised in order to obtain a smooth surface with the desired shape. Their use in micromotors/ microgenerators has been tested.
International
Si
JCR
Si
Title
J IRON STEEL RES INT
ISBN
1006-706X
Impact factor JCR
0,202
Impact info
Volume
13
Journal number
0
From page
240
To page
251
Month
SIN MES
Ranking
Participants
  • AUTOR: A. HERNANDO
  • AUTOR: F.J. PALOMARES
  • AUTOR: JJ ROMERO (UCM)
  • AUTOR: J.M. GONZALEZ
  • Autor: Federico Alberto Cebollada Baratas (UPM)
  • AUTOR: F. PIGAZO
  • AUTOR: R SASTRE
  • AUTOR: R. CUADRADO
Research Group, Departaments and Institutes related
  • Creador: Grupo de Investigación: Propiedades ópticas, eléctricas y magnéticas de materiales y sus aplicaciones (POEMMA)
  • Departamento: Física Aplicada a las Tecnologías de la Información
S2i 2019 Observatorio de investigación @ UPM con la colaboración del Consejo Social UPM
Cofinanciación del MINECO en el marco del Programa INNCIDE 2011 (OTR-2011-0236)
Cofinanciación del MINECO en el marco del Programa INNPACTO (IPT-020000-2010-22)