Plate-like SrFe12O19 particles prepared by modified sol–gel method

• Fine SrFe12O19 plate-like particles were synthesized by the modified sol–gel method.
• Powders prepared at T =790–850 °C (1 h) are pure M-type strontium hexaferrite.
• High values of HC=6.2–6.4 kOe and MS=71–72 emu/g have been obtained.

M-type strontium hexaferrite powders were synthesized by the modified sol–gel method with calcination in NaCl matrix in a temperature range 790–850 °C for 1 h. X-ray diffraction analysis shows the formation of pure M-type strontium hexaferrite phase. The SrFe12O19 particles have a plate-like shape with a mean diameter 130–185 nm and a thickness 45–55 nm. The prepared powders show a saturation magnetization 70–72 emu/g and a coercive force 6.0–6.4 kOe. The suggested synthesis method combines simplicity, using of low calcination temperatures and allows to synthesize pure strontium hexaferrite powders with excellent hard magnetic properties.