Mn-Zn ferrites have wide applications in industry. Since the early history of Mn-Zn ferrites, it has been found that combination of high permeability (?) and high permittivity (?) of Mn-Zn ferrites may cause dimensional effects in Mn-Zn ferrite-core-based magnetic devices to deteriorate the performance above a few hundred kHz. Both ? and ? are critical parameters for performance examination and optimization of those magnetic devices when the size of the ferrite core is comparable to the wavelength in the core. However, the Mn-Zn ferrites' ? and ? measured by using conventional methods are dimension-dependent due to dimensional effects, thus different from the intrinsic, or dimensional-independent, values. In this book, the methods are investigated theoretically and experimentally to determine Mn-Zn ferrites' dimension-independent ? and ?. The book should help to understand dimensional effects, and to shed a light on the principle and the technique to determine Mn-Zn ferrites' dimension-independent ? and ?, and should be useful to students, engineers and researchers in materials science and electrical engineering who are working in the areas related to Mn-Zn ferrites.
Ruifeng HUANG, Electrical Engineering: PhD degree from Nanyang Technological Univ., Singapore. Research Scientist in Temasek Laboratories at National University of Singapore. Daming ZHANG, Power Engineering: PhD degree from Nanyang Technological Univ.. Assistant Professor in Power Division of school of EEE at Nanyang Technological Univ..