Effect of Microstructure on the Coercivity of SmCo5 Intermetallic Compound

SmCo5 is well known for its high coercive properties. This property helped the compound to become stable even at high temperatures. A lot of efforts had been made to improve this important property but so far only a few percentages of the theoretical coercivity values were achieved. Improving processing parameters or doping by other alloying elements are two popular ways to manipulate the properties of SmCo5. In this research work, the cooling temperature of the indigenously developed water-cooled copper mold was manipulated to control the solidifying peritectic structure. The obtained casting was milled to powder and the final sintered product was produced. It was noted that high coercive values i.e. 32.9 kOe was achieved at low water inlet temperature. The results were interpreted by using a scanning electron microscope (SEM), Differential thermal analysis and X-Ray diffraction analysis. SEM results revealed peritectic nano-structure in SmCo5 compounds. These nano-structures seem helped to improve the coercivity of SmCo5.