Comparative Analysis of Sintering Mn_(0.65)Zn_(0.35)Fe_2O_4 Ferrite by Microwave Energy and N_2 Atmosphere

摘要

Research in Mn-Zn ferrites have been growing in recent years, mainly because of the properties in high frequency application such as high saturation magnetization, low core losses, which are sensitive to the structure, processing conditions, such as sintering temperature, time and atmosphere. This study aims to evaluate the microstructure and magnetic characteristics Mn_(0.65)Zn_(0.35)Fe_2O_4 ferrite sintered in N_2 atmosphere and to microwave energy at 1200°C/2h. The samples were compacted by uniaxial pressing at 200 MPa and sintered in a microwave oven with a heating rate of 50°C/min and sintering time of 30 min. For samples sintered in N_2 atmosphere was used heating rate of 5°C/min with sintering time of 2 hours. The samples were characterized by apparent and bulk density, XRD, SEM and magnetic measurements. The results indicate the formation single phase of Mn-Zn ferrite for sample sintering in N_2 atmosphere, and to sintering by microwave oven observed the phase ferrite Mn-Zn with trace of secondary phase hematite. The density and saturation magnetization were 3.14 and 3.12 g/cm~3, 5 and 83 emug~(-1) for the samples sintered by microwave energy and N_2 atmosphere respectively.