铬系分相青釉的制备及呈色机理研究

Preparation and Coloration Mechanism of Chromium Phase Glaze

以Cr_2O_3为着色剂,代替传统青釉中的Fe_2O_3,并以磷酸钙为分相促进剂,成功制备出了与古钧瓷天青釉色相近的分相青瓷釉。利用色度仪、XRD、FT-IR、SEM和EDS,研究了不同磷酸钙加入量对釉色及微观结构的影响,并分析了其呈色机理。结果表明:引入磷酸钙后,釉熔体生成的晶体含量增多,使得釉面乳浊度增强。同时,釉中的分相液滴尺寸逐渐减小,使得瑞利散射现象产生的乳光蓝色加深,两者综合作用,减弱了Cr^(3+)绿,从而呈现出蓝青色调。然而,当磷酸钙加入量过多时,大量的羟基磷灰石晶体阻碍了瑞利散射,釉面呈现出青白色。

The separative-phase celadon glaze similar to the ancient Jun glaze was successfully prepared using Cr2O3 as a colorant instead of Fe2O3 in traditional celadon together with calcium phosphate as a phase accelerator. The effects of the calcium phosphate content on the color and microstructure of the separative-phase celadon glaze were characterized by colorimeter, XRD, FT-IR, SEM, and EDS. Furthermore, the coloration mechanism of the separative-phase celadon glaze with Cr2O3 as a colorant was also analyzed. The results indicated that the crystal content in glaze melt increases with the introduction of calcium phosphate, which further enhances the opacity of the glaze. Meanwhile, the size of phase separative droplets in the glaze decreases and then darkens the blue opalescence caused by the Rayleigh scattering phenomenon. Both factors weaken the green color of Cr^3＋ and accelerate the glaze color transformation into dark purplish blue. However, the high content of hydroxyapatite crystals hinders the occurrence of the Rayleigh scattering with addition of excessive calcium phosphate. Therefore, the glaze color gradually turns bluish white.