Effects of heat treatment on the microstructure and magnetic properties of electrodeposited Ni-Fe permalloy foils

Electrodeposited Ni-Fe permalloy foils was annealed under hydrogen atmosphere at 850, 1000 and 1 150 ℃ for 5 h, respectively. The microstructures of cross-sections and surfaces were observed by SEM and optical microscope, the crystal structure was studied by XRD, and the direct-current magnetic properties were measured by direct-current magnetic properties testing equipment. The results indicate that when the annealing temperature is between 850 and 1 150 ℃, the direct-current magnetic properties improve with increasing temperature. After annealing, the crystals of the permalloy foils grow up rapidly and present obvious preferred orientation.