Microstructures and magnetic and electric properties of low-temperature sintering Mn-Zn ferrites without and with addition of lithium borosilicate glass

Highly sinterable Mn-Zn ferrite powder consisting of submicrometer-size particles (approx. 0.18 μm) with structural distortion has been prepared by grinding a coprecipitated powder with a media agitation mill. Dense pure Mn-Zn ferrites (>98% of theoretical) can be fabricated by heating at 900°C in a nitrogen atmosphere. They show magnetic and electric properties in which their permeability μ and electric resistivity ρ are 520-635 and 0.8-1.6 Ω m, respectively. These properties have been further improved by adding small amounts of lithium borosilicate glass; especially, high values of μ = 1015 and ρ = 474 Ω m are achieved in ferrites (900°C/12 h) with 0.1 wt% glass addition. The microstructures consist of large grains (approx. 35 μm) with high resistive layers at grain boundaries.