Date of Award
Master of Science
Materials Science and Engineering
There are many instances where it is desirable to absorb specific frequencies of microwave radiation. Areas of interest include radar applications, enhancing the performance of cell phones, and in microwave-assisted curing of thermosets. An alternative to the current use of ferromagnetic particles dispersed in a matrix is to take advantage of dielectric relaxation due to interfacial polarization as the means of electromagnetic absorption.;Three composite materials composed of polydisperse electroless, polydisperse sputtered, or monodisperse electroless nickel-coated particles are examined for their electromagnetic properties in the microwave range. Complex permittivity and permeability as a function of frequency and volume fraction are presented. These results are compared against the theoretical real and imaginary permittivity calculated using the effective medium theories of Sihvola-Lindell, Harfield, and Hanai-Bruggeman. The microwave absorbing properties of these composites as a function of thickness and frequency are then compared.
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/
Nathan Lee Fischer
Fischer, Nathan Lee, "Novel composites for microwave absorption" (2008). Retrospective Theses and Dissertations. 15311.