针对坭兴陶原料中含有一定量方解石的特点,通过调节方解石在泥料中的含量,在氧化条件下和不同温度下烧制成不同的试样,研究了方解石含量对试样线收缩率、吸水率、体积密度以及抗折强度的影响,采用XRD和SEM分别对试样的物相和微观结构进行了观察分析。结果表明:随着方解石含量的增加,坭兴陶的吸水率增大,线收缩率、体积密度和抗折强度减小;随着方解石含量的增加,烧结体中孔洞的数量增多且尺寸增大,孔的形态由不规则的封闭孔转变为圆形封闭孔后再转化为不规整的连通孔;并且液相黏度逐渐降低,结晶相逐渐增多,并由硅灰石相向铝方柱石和硅灰石共晶相转变,石英含量逐渐降低。
According to the Nixing pottery raw with calcite, the various sample were sintered at different temperature and under oxidizing conditions by adjusting content of calcite in the raw. The effects of calcite content on linear shrinkage, water absorption, volume density and flexural strength of Nixing pottery were studied. The mineral composition and microstructure of the samples were analyzed by XRD and SEM. The results show that, the water absorption increased, and the linear shrinkage, volume density and flexural strength of Nixing pottery decreased. With the increase of calcite contents, the number of pores and their size increased, and the pore's morphology changed from closed irregular to closed circular, and then converted to the irregular interconnected pores. Also, liquid phase viscosity decreased and the crystalline phase increased gradually, the phase transformation was from the wollastonite to the eutectic phase of gehlenite and wollastonite, and with the quartz decreasing gradually in the sintered samples.