Structure and Magnetic Properties of Spark Plasma Sintered NdFeB

A spark plasma sintering technique was used to consolidate NdFeB compacts at four different temperatures as 750°C, 850°C, 950°C and 1030°C. The surface of specimens was polished to remove the carbon paper on the surface of NdFeB compacts by using SiC paper for up to #1500 in grit. The polished NdFeB compacts were then magnetized by using impulse magnetizer K-series. In this study, the effects of temperature on the structure and magnetic properties of NdFeB magnet were studied. The results show that depending on the fabrication temperature, the X-ray diffraction patterns of NdFeB compacts are distinct. This suggests that the structure of NdFeB compacts is changed with increase in fabrication temperature. Meanwhile, the remanance Br and energy product BH(max) of NdFeB magnets tend to decrease as fabrication temperature increase.