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Title: Magnetostriction of field-structured magnetoelastomers.

Abstract

Field-structured magnetic particle composites are an important new class of materials that have great potential as both sensors and actuators. These materials are synthesized by suspending magnetic particles in a polymeric resin and subjecting these to magnetic fields while the resin polymerizes. If a simple uniaxial magnetic field is used, the particles will form chains, yielding composites whose magnetic susceptibility is enhanced along a single direction. A biaxial magnetic field, comprised of two orthogonal ac fields, forms particle sheets, yielding composites whose magnetic susceptibility is enhanced along two principal directions. A balanced triaxial magnetic field can be used to enhance the susceptibility in all directions, and biased heterodyned triaxial magnetic fields are especially effective for producing composites with a greatly enhanced susceptibility along a single axis. Magnetostriction is quadratic in the susceptibility, so increasing the composite susceptibility is important to developing actuators that function well at modest fields. To investigate magnetostriction in these field-structured composites we have constructed a sensitive, constant-stress apparatus capable of 1 ppm strain resolution. The sample geometry is designed to minimize demagnetizing field effects. With this apparatus we have demonstrated field-structured composites with nearly 10,000 ppm strain.

Authors:
 [1]; ; ; ; ;
  1. (Dominican University, River Forest, IL)
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
877143
Report Number(s):
SAND2005-8032
TRN: US200606%%714
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 42 ENGINEERING; ELASTOMERS; MAGNETOSTRICTION; ACTUATORS; MAGNETIC SUSCEPTIBILITY; RESINS; STRAINS; SYNTHESIS; Magnetosphere.; Magnetic fields.; Magnetic devices.

Citation Formats

Gulley, Gerald L., Read, Douglas H., Martin, James Ellis, Huber, Dale L., Anderson, Robert Alan, and Frankamp, Benjamin L. Magnetostriction of field-structured magnetoelastomers.. United States: N. p., 2005. Web. doi:10.2172/877143.
Gulley, Gerald L., Read, Douglas H., Martin, James Ellis, Huber, Dale L., Anderson, Robert Alan, & Frankamp, Benjamin L. Magnetostriction of field-structured magnetoelastomers.. United States. doi:10.2172/877143.
Gulley, Gerald L., Read, Douglas H., Martin, James Ellis, Huber, Dale L., Anderson, Robert Alan, and Frankamp, Benjamin L. Thu . "Magnetostriction of field-structured magnetoelastomers.". United States. doi:10.2172/877143. https://www.osti.gov/servlets/purl/877143.
@article{osti_877143,
title = {Magnetostriction of field-structured magnetoelastomers.},
author = {Gulley, Gerald L. and Read, Douglas H. and Martin, James Ellis and Huber, Dale L. and Anderson, Robert Alan and Frankamp, Benjamin L.},
abstractNote = {Field-structured magnetic particle composites are an important new class of materials that have great potential as both sensors and actuators. These materials are synthesized by suspending magnetic particles in a polymeric resin and subjecting these to magnetic fields while the resin polymerizes. If a simple uniaxial magnetic field is used, the particles will form chains, yielding composites whose magnetic susceptibility is enhanced along a single direction. A biaxial magnetic field, comprised of two orthogonal ac fields, forms particle sheets, yielding composites whose magnetic susceptibility is enhanced along two principal directions. A balanced triaxial magnetic field can be used to enhance the susceptibility in all directions, and biased heterodyned triaxial magnetic fields are especially effective for producing composites with a greatly enhanced susceptibility along a single axis. Magnetostriction is quadratic in the susceptibility, so increasing the composite susceptibility is important to developing actuators that function well at modest fields. To investigate magnetostriction in these field-structured composites we have constructed a sensitive, constant-stress apparatus capable of 1 ppm strain resolution. The sample geometry is designed to minimize demagnetizing field effects. With this apparatus we have demonstrated field-structured composites with nearly 10,000 ppm strain.},
doi = {10.2172/877143},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Dec 01 00:00:00 EST 2005},
month = {Thu Dec 01 00:00:00 EST 2005}
}

Technical Report:

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