GHAIDER AHMADOPOUR - Materials Engineering Department, Malek Ashtar University of Technology, Shahin Shahr, Isfahan, Iran,
ALI GHASEMI - Materials Engineering Department, Malek Ashtar University of Technology, Shahin Shahr, Isfahan, Iran,
EBRAHIM PAIMOZD - Materials Engineering Department, Malek Ashtar University of Technology, Shahin Shahr, Isfahan, Iran,

Spinel ferrite with the composition of Nios-CuZno.4Fe2O4 (x= 0 - 0.5 with a step of 0.1) were prepared by a sol-gel and sol-gel auto-combustion method. X-ray powder diffractometery, scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometer were used to the structural and magnetic properties nanoparticles. The employing of citric acid in combustion process could greatly affect on the size of nanoparticles. It was found that the amount of copper in Nios-Cu,Zno.4Fe2O4 fertite affect on particle size. The synthesis nanoparticles by combustion have superparamagnetism behavior. With an increasing in Cui content, magnetization and the blocking temperature increase. The phenomenological Néel - Brown and Vogel - Fulcher models were employed to distinguish between the interacting or non-interacting system. The parameters obtained for the Vogel - Fulcher equation indicate that there is strong interaction between nanoparticles.

Ni-Zn ferrite, sol-gel auto-combustion, Magnetic properties, cu-substituted