Current Research Projects
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.