The sintering behavior of BaFe12O19 with the addition of one and three weight % of CuWO4 as a liquid phase sintering aid is studied. Samples are sintered in the temperature range 900-1250 oC and the effect of CuWO4 addition on density, microstructure, phase composition and magnetic properties is examined. Compared to BaFe12O19 with no sintering aid addition, addition of 1 wt % CuWO4 retards densification. Addition of 3 wt % CuWO4 promotes densification at lower sintering temperatures but retards densification at temperatures > 1050 oC. Three wt % CuWO4 addition induces the formation of BaWO4 and Ba3WFe2O9 secondary phases at temperatures ≥ 1100 oC. Addition of CuWO4 causes a decrease in saturation magnetization, remanent magnetization and coercivity.
Keywords: Ferrites, Magnetic properties, Liquid phase sintering, Microstructure, Hard magnets.