Fabrication of nano-sized BaxMg1−xFe2O4 ferrite powders by using self-propagating high temperature synthesis reaction and mechanical milling

Nano-sized BaxMg1−xFe2O4 ferrite particles less than about 150 nm were prepared by using self-propagating high temperature synthesis (SHS) and mechanical ball milling. As the ratio of BaO2 to MgO in the initial powder composition varied from 0.25 to 4.0, coercive force (iHc) decreased about 102%, whereas, maximum magnetization (Ms) and residual magnetization (Mr) increased about 324% and 221%, respectively. Oxygen pressure changes from 0.25 to 1.0 MPa during SHS reaction resulted in decreasing iHc about 46%, whereas, increasing Ms and Mr about 59% and 4%, respectively. An empirical equation to describe the SHS reaction with oxygen pressure was obtained.