P. Quiroz, B. Halbedel, A. Bustamante, J.C. González
Hyperfine Interact, 202 (2011) 97-106
doi: 10.1007/s10751-011-0361-1

A series of M-type barium hexaferrite has been synthesized in a glass melt by partially substituting the Fe₂O₃ with TiO₂ for investigation of their structure. The glass melt has the basic composition (mol%): 40 BaO + 33 B₂O₃ + (27-x) Fe₂O₃ + x TiO₂ with x = 0, 3.6, 5.4 and 7.2 mol% TiO₂. The substituted ferrites were studied by means of X-ray diffraction, Mössbauer spectroscopy and vibration sample magnetometer. X-ray diffraction studies revealed that not all samples have a single ferritic phase, a small second phase corresponding to BaTi₆O₁₃ was also observed to form. The Mössbauer spectra changed from magnetically ordered (x = 0) to magnetically ordered with strong line broadening. Moreover, the broadening increases with TiO₂ content. The Mössbauer parameters suggested that Ti^4 + occupies the 2a and 12k crystal sites, and the Ti^4 + substitution on the 2b and 4f₂ site also occurs at high melt dopings. Therefore, coercivity and saturation magnetization decreased.