Magnetic properties of hexagonal isotropic polycrystalline SrFe₁₂O₁₉ ferrites obtained by radiation-thermal sintering  

The phase composition and lattice parameters of the specimens have been studied using X-ray diffraction on a DRON-8 diffractometer in CoK_α1 radiation. The density of the specimens has been measured following Archimedean law on a UW620H electronic balance with a liquid density measurement attachment. The magnetic hysteresis loop parameters of the specimens have been studied with a VM-07 vibromagnetometer.

The specimens has proven to be single-phase with a P63/mmc space group (No. 194), corresponding to a hexagonal ferrite structure. For the first time, changes in the magnetic hysteresis loop parameters of hexagonal SrFe₁₂O₁₉ strontium ferrite specimens synthesized with fast electron beam RTS have been studied. We show that the width and intensity of the magnetic hysteresis loop decrease noticeably with an increase in the RTS temperature from 1200 to 1350–1400 °C. The magnetization coercive force _jH_c decline to the minimum values at RTS temperatures T_sint ≥1250 °C, probably due to recrystallization in the ferrite lattice: the combined impact of RTS temperature and radiation-induced diffusion triggers intense grain growth, significantly reducing the number of domain boundaries and, hence, causing a drop in _jH_c. The high energy efficiency of RTS in ferrite ceramics synthesis has been confirmed for the example of SrFe₁₂O₁₉.