Phase formation, grain growth and magnetic properties of NiCuZn ferrites

► Solid-state reaction equations of NiCuZn ferrites for iron-stoichiometric, iron-excessive, and iron-deficient composition. ► X-ray diffraction peaks first shift towards lower angle and then slightly move to higher angle with increase of iron content. ► Iron-deficient composition favors to promote grain growth and densification. ► Iron-stoichiometric NiCuZn ferrite shows the optimal magnetic property.