ZnO varistors doped with Bi₂O₃, Sb₂O₃, CoO, MnO₂ and Cr₂O₃ were prepared separately by two mixing processes: conventional and masterbatching mixed-oxide process method. After the mixing process, the ZnO-based varistor powders were milled using planetary ball mill at 200, 300, 400 and 500 rpm. Particle size analysis and XRD analysis were used to study the differences after milling process in ZnO-based varistor powder. The particle sizes of varistor powder were reduced and new compound encountered after milling process.
