The CoFeub>2ub>Oub>4ub>/CoFeub>2ub>/SiOub>2ub> nanocomposites with exchange coupling behavior were prepared.
The hysteresis loop of the sample T6 behaved like a single magnetic phase.
The values of the saturation magnetization and coercivity of T6 were higher than those of pure CoFeub>2ub>Oub>4ub>/CoFeub>2ub>.