Sintering of High Density Ferrites
Low melting eutectic compositions in MnZnTi ferrites, in the amount of 0.2 – 10 wt%, are used to promote sintering at low temperatures. The unique aspects of this approach are the use of low melting point eutectics per se and that the source of the low melting composition is derived from components which are normally part of the ferrite composition. During oxygen sintering, a second phase of the hematite structure is stablized by the TiO2 content in ferrites. After the hematite phase is reduced by appropriate nitrogen anneal, dense-single phase ferrites with uniformly large grains can be formed at temperatures as low as 1250°C.
KeywordsOxygen Partial Pressure Spinel Phase Dopant Content Nickel Ferrite Transient Liquid Phase
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