Structure and magnetic properties of bulk Fe56Co7Ni7Zr10B20 magnetic alloy fabricated by spark plasma sintering

Bulk nanocrystalline Fe56Co7Ni7Zr10B20 magnetic alloys of 10 mm in diameter and 3 mm in thickness were prepared by the spark plasma sintering method. The microstructure, thermal behavior and magnetic properties of the specimens were investigated by X-ray diffraction, differential scanning calorimetry, magnetic force microscopy, transmission electron microscopy and vibrating sample magnetometer. It is found that dense sintered materials with optimal magnetic properties could be obtained at the appropriate sintering temperature. Namely, as sintering temperature is 1150 K, the saturation magnetization and relative density of sintered materials are up to 1.45 T and 93.3%, respectively. An average grain size of ∼40 nm of α-Fe crystallites has been obtained in the specimen sintered at 1150 K.