Journal of the American Ceramic Society, Vol.102, No.8, 4757-4764, 2019
Fabrication and characterization of IR-transparent Fe2+ doped MgAl2O4 ceramics
Initial investigations on the preparation of highly transparent Fe2+:MgAl2O4 ceramics using nanopowders synthesized in a laser plume were carried out. For the first time, dense Fe2+:MgAl2O4 ceramics with high transmission in the mid-IR range were fabricated at a temperature as low as 1300 degrees C and with a short sintering time (1 hour). The obtained Fe2+:MgAl2O4 ceramics contain a secondary (MgO)(0.91)(FeO)(0.09) phase with a low wt% content, causing a substantial decrease in transmittance in the visible range. The transmittance increases with an increase in wavelength due to a decrease in Rayleigh scattering and reaches 85.6% at lambda = 4 mu m, which is close to the theoretical value. The absorption cross section of divalent iron ions was estimated to be sigma = (1.66 +/- 0.14) x 10(-20) cm(2).