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 Determination of Commercial
Feasibility of Magnetic Refrigeration
An instrumented, room-temperature magnetic refrigerator is current being
constructed in the Institute's laboratories. It will be used to study the
feasibility of magnetic refrigeration as an alternative to freon-based
units in widespread commercial applications. This work is funded by the
NSF.
Gaining an Understanding of the
Bimodal Behavior of Co-Pt Multilayer Material
Some Co-Pt multilayer have unexpectedly been found to exhibit 2-step, or
bimodal, magnetization reversal behavior. This Phenomenon is being
documented through the use of magneto-optical Kerr effect (MOKE)
measurements and indicator film imaging techniques. An understanding of the
reason for the behavior, the make-up of the multilayers in which it does
and does not occur, and methods for the reliable manufacturing and use of
these types of magneto-optical materials is currently being pursued. This
work done in collaboration with IBM is funded by NSF and NIST.
Modeling of Magnetic Properties
and Magnetic Aftereffect in Multilayer Materials
A modified Preisach-Arrhenius model is being developed to predict magnetic
aftereffect behavior in multilayer materials exhibiting perpendicular
magnetization. This theoretically predicted data is then compared to
experimental data obtained in the MOKE apparatus to test the validity of
the modeling.
Development and Verification of
a Vector Preisach Modeling
Experimental 3-dimensional measurements are being made on magnetic recording
material in the IMR VSM, to experimentally verify the correct operation of
a simplified vector Preisach magnetization model. This model will be
further refined to increase its speed of computation so that it may be used
in FEM computations or speed sensitive control applications.
Development and Verification of
Standard Micromagnetics Problems
Work on various micromagnetic modeling problems is conducted in
collaboration with NIST, with particular emphasis on developing standard
micromagnetic problems and standardized micromagnetic modeling code.
Incorporation of Magnetic
Hysteresis Properties into ANSYS Finite Element Software
ANSYS finite element software is in worldwide use for structural, thermal,
fluid, electromagnetic and coupled field analysis and design problems. The
electromagnetic analysis capabilities, however, do not allow for the use of
materials with realistic magnetic hysteresis properties. ANSYS has funded
the Institute to include the ability to simulate magnetic hysteresis based
on measured material characteristics within their FEM program.
Modeling and Control of
Magnetostrictive Materials
Magnetostrictive materials used in underwater transducers have the potential
for high power output, but have signal distortion problems due to their
highly nonlinear strain-applied field properties. The accurate modeling of
this magnetostrictive behavior and the development of an inverse model of
this behavior is underway within the IMR, with the intent to control the
nonlinear behavior of magnetostrictive material used in Navy transducers
and projectors.
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