Abstract
The effect of additives on the orientation of magnetic Sr-ferrite powders has been studied during powder injection molding under applied magnetic field for fabricating multi-pole anisotropic sintered Sr-ferrite magnets. The orientation of the Sr-ferrite powders depends sensitively on the fluidity of powder-binder mixture, related to the binder additives and the injection molding temperature, and the magnetic field intensity. The orientation of Sr-ferrite powders is good for the compacts with stearic acid added in the binder system of paraffin wax/carnauba wax/HDPE, but it is poor for the compacts with silane coupling agent added. The orientation of Sr-ferrites higher than 80% is achieved at the following useful conditions; apparent viscosity lower than 2500 poise in 1000 sec-1 shear rate and applied magnetic field higher than 4 kOe.
| Original language | English |
|---|---|
| Pages (from-to) | 240-245 |
| Number of pages | 6 |
| Journal | Polymer (Korea) |
| Volume | 25 |
| Issue number | 2 |
| State | Published - 2001 |
Keywords
- Coupling agent
- Fluidity
- Orientation of Sr-ferrites
- Powder injection molding
- Stearic acid