Effect of Annealing on the Microstructure and Magnetic Properties of 2J4 Alloy

The effect of annealing on the microstructural characterization and magnetic properties of 2J4 alloy has been investigated.The alloys were annealed in argon atmosphere for 0.5h at different temperatures.The results indicated that there were some precipitated phases afer annealing,which can pin domain boundary movement, thus leading to improved magnetic energy product and hysteresis properties due to enhanced coercivity and remanence. Magnetic domain morphology showed that the number of domains increased after heat treatment, the exchange energy between magnetic domains and the energy of magnetocrystalline anisotropy increased with increasing domain number,thus leading to better coercivity. With increasing temperature from 620°C to 680°C, saturation magnetization increased at first, and then decreased under the effect of increase in precipitates and decrease in strain and dislocations. The coercivity,hysteresis loss and ratio of the remanence to saturation magnetization keeped increasing due to increase of tiny and dispersed precipitates. This study can provide theoretically a reliable way for preparing 2J4 magnetic alloys with high performance.