Effect of Stress on Magnetic Property of the SiO2-Added MnZn Ferrites

In this work, the SiO2-added MnZn power ferrites have been prepared by the conventional ceramic method, and the effect of stress on initial permeability and power loss has been investigated. With increasing SiO2 content, initial permeability firstly increases and then decreases, whereas power loss firstly decreases and then increases. The sample with 50 ppm SiO2 additive exhibits optimal magnetic performance, including the highest initial permeability and the lowest power loss. This optimal sample also exhibits the wide-temperature characteristics of power loss. Initial permeability decreases and power loss increases under the applied stress. The sample with 75 ppm SiO2 additive exhibits the best stress insensitivity of initial permeability and power loss. Through the loss separation method, it is revealed that magnetic hysteresis loss is more sensitive whereas eddy current loss remains almost unchanged with stress. An appropriate addition of SiO2 reduces the stress sensitivity of the initial permeability and power loss of MnZn ferrites.