YU Changfeng, ZHU Xiaoping, LI Xing, ZHANG Xiaojun

(School of Materials Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen, Jiangxi 333001, China)

Abstract: Cobalt -free Fe -Mn -Cr -Ni black pigment was prepared with vanadium tailings, copper oxide, nickel oxide, and chromium oxide as main materials. With the amount of vanadium tailings set at a definite level, the ratios of oxides were adjusted to observe the effects of various oxides on the black pigment to determine its composition and synthesis conditions. Then, the cobalt-free black pigment was prepared. Experiment results show that the pretreatment of vanadium tailings and the particle size of the pigment have significant effects on the colour generation of the cobalt -free pigment. The XRD characterization of the synthesized samples reveals that the synthetic pigment belongs to the Fe-Mn-Cr-Ni system in spinel structure. The synthetic pigment has a good adaptability to high -melting glazes, especially feldspar glaze. The addition of the pigment to this glaze will result in a smooth shiny black surface. The composition of the glaze used is k -feldspar 35%, sodium feldspar 15%, quartz 10%, limestone 15%, dolomite 10%, china stone 10%, strontium carbonate 5%, and black pigment 6%, respectively. Fired at the temperature of 1260°C and soaked for 10min, the glaze has good body-glaze fit, thermal stability, glossiness and glazing result. The results also show that the generated colour will be more homogeneous and the glazing surface will be smoother when the pigment is ground into particles of smaller size.

Key words: vanadium tailings; cobalt-free black pigment; high-temperature black pigment