 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. |
