Study Of M-type Calcium Ferrite On The Structural And Magnetic Properties

Permanent magnetic material is one of the indispensable national economy based materials. In the family of the permanent magnetic materials, although the integrated magnetic of the ferrite is low, but because of the rich raw material, the low average selling price, the lowest cost of the unit of magnetic energy product, the simple mature technology and no oxidation problem, It is still the most ideal permanent magnetic material in car dc motors, start motor, mean gap magnetic connector, audio converter, separator, suck the device and many other application fields. Since the50s, the world hard ferrite batch production and the momentum of development, the output value of about1.5times of rare earth permanent magnet. Expected to come a long period of time, it will continue to be the most widely used and the biggest demand of permanent magnetic material.M-type ferrite material has high calcium coercive force, large saturation magnetization strength, stable in chemical, good wear resistance and corrosion resistance. And because of the low cost price, it has cost-effective and wide prospect of market.Ferric oxide and calcium carbonate as raw material, using wet ball mill and wet pressure magnetic field forming, through the ceramic method prepared for high performance of M-type calcium ferrite. Using the X-ray diffraction (XRD) analysis the structures of samples, transmission electron microscope characterizations the morphology of samples, vibration sample magnetic field meter analysis the magnetic of samples. The main research the M-type calcium in different temperature ferrite beforehand to burn, the structure of the samples, as well as phase change process; Whether the added magnetic field intensity size can influence the magnetic of the sample; And the influence of secondary additives and dispersants to the magnetic properties of the sample.We have got these conclusions:the sample Sr0.8Ca0.2Fe12O19joining the best secondary additives of0.8wt%A12O3,0.2wt%SiO2,0.3wt%H3BO3,0.8wt%calcium gluconate, dispersants adding amount of calcium gluconate for0.8wt%, wet forming in magnetic field and then sintering, we can obtain higher magnetic:esidual flux density (BT=0.430T),intrinsic coercivity (Hcj=382.2kA/m), magnetic induction coercivity(Hcb=315.0kA/m) and maximum energy product [(BH)max=30.8kJ/m3].