Novel highly elastic magnetic materials for dampers and seals: part II. Material behavior in a magnetic field

The combination of polymers with magnetic particles displays novel and often enhanced properties compared to the traditional materials. They can open up possibilities for new technological applications. The magnetic field sensitive elastomers represent a new type of composites consisting of small particles, usually from nanometer range to micron range, dispersed in a highly elastic polymeric matrix. In this paper, we show that in the presence of built-in magnetic particles it is possible to tune the elastic modulus by an external magnetic field. We propose a phenomenological equation to describe the effect of the external magnetic field on the elastic modulus. We demonstrate the engineering potential of new materials on the examples of two devices. The first one is a new type of seals fundamentally different from those used before. In the simplest case, the sealing assembly includes a magnetoelastic strip and a permanent magnet. They attract due to the magnetic forces. This ensures that due to high elasticity of the proposed composites and good adhesion properties, the strip of magnetoelastic will adopt the shape of the surface to be sealed, this fact leading to an excellent sealing. Another straightforward application of the magnetic composites is based on their magnetic field dependent elastic modulus. Namely, we demonstrate in this paper the possible application of these materials as adjustable vibration dampers. Copyright © 2007 John Wiley & Sons, Ltd.

[1]  M. Zrínyi,et al.  Magnetic field sensitive functional elastomers with tuneable elastic modulus , 2006 .

[2]  John Matthew Ginder,et al.  MAGNETOSTRICTIVE PHENOMENA IN MAGNETORHEOLOGICAL ELASTOMERS , 2002 .

[3]  Toshio Kurauchi,et al.  Magnetroviscoelastic behavior of composite gels , 1995 .

[4]  G. Zhou,et al.  Shear properties of a magnetorheological elastomer , 2003 .

[5]  S. Bednarek.  The giant magnetostriction in ferromagnetic composites within an elastomer matrix , 1999 .

[6]  Alexei R. Khokhlov,et al.  Effect of a homogeneous magnetic field on the mechanical behavior of soft magnetic elastomers under compression , 2006 .

[7]  Zhenyu Jiang,et al.  Deformation in magnetorheological elastomer and elastomer?ferromagnet composite driven by a magnetic field , 2004 .

[8]  O. Bruno,et al.  On the magneto-elastic properties of elastomer–ferromagnet composites , 2001 .

[9]  M. Zrínyi,et al.  Thermotropic Polymer Gels: Smart Gel Glass , 2005 .

[10]  Miklós Zrínyi,et al.  Ferrogel: a new magneto-controlled elastic medium , 1997 .

[11]  Miklós Zrínyi,et al.  Deformation of ferrogels induced by nonuniform magnetic fields , 1996 .

[12]  M. Zrínyi,et al.  Electric and Magnetic Field‐Structured Smart Composites , 2005 .

[13]  J. Carlson,et al.  MR fluid, foam and elastomer devices , 2000 .

[14]  R. Sherwood,et al.  Optically Transparent, Electrically Conductive Composite Medium , 1992, Science.

[15]  J. Calvert,et al.  Interaction of metallized tubules with electromagnetic radiation , 1990 .

[16]  K. Koyama,et al.  COMPRESSIVE MODULUS OF FERRITE CONTAINING POLYMER GELS , 2002 .

[17]  M. Zrínyi,et al.  Direct observation of abrupt shape transition in ferrogels induced by nonuniform magnetic field , 1997 .

[18]  S. Bednarek.  Magnetoelastic properties of a ferroelast within an organo-silicon polymer matrix , 1997 .

[19]  Robert A. Anderson,et al.  Electrostriction in field-structured composites: Basis for a fast artificial muscle? , 1999 .

[20]  Mark R. Jolly,et al.  The Magnetoviscoelastic Response of Elastomer Composites Consisting of Ferrous Particles Embedded in a Polymer Matrix , 1996 .