Effect of mineralizer on the synthesis of (Ni, Mn) co-doping CuFe5O8 pigment and its glazing performance

Novel Co and Cr free, high-temperature (Ni, Mn) co-doping CuFe5O8 black ceramic pigments were synthesized. The effects of mineralizer type and mineralizer amount on the synthesis and coloration of (Ni, Mn) co-doping CuFe5O8 pigments, as well as the effect of glazing calcination temperature on glaze coloration were systematically investigated using testing and characterization methods such as XRD, FE-SEM, TEM, EDS-mapping, HAADF and colorimeter. The results indicate that compared with H3BO3, NH4F, LiF and NaF mineralizers, the pigment with MgO as the mineralizer is relatively better. The optimized mineralizer MgO amount is 6.25 wt.% (mass ratio relative to the pigment). L*, a* and b* values of corresponding optimized pigment are 21.36, 1.10 and -0.24, respectively. The crystal phase of the pigment is CuFe5O8 (73–2314), and no diffraction peak of the heterophase is detected. The crystal size of the pigments is 0.8–1.5 μm with excellent dispersivity. The glazing temperatures have little effect on the coloration of the pigments when they are used at 1000 °C, 1150 °C and 1300 °C. The results show that the pigment has excellent high temperature resistance and is expected to be widely used in high-temperature glazing coloration.