故宫清代年款琉璃瓦釉的成分及相关问题研究

The Research on the Component of the Glass Tile Glaze and the Related Problems as Model Year in the Qing Dynasty in the Imperial Palace

在故宫古建大修中发现一批带有清代年款的琉璃瓦件,这些瓦件的制作原料、烧制工艺反映了当时的技术水平,同时也反映了国家对建筑琉璃生产的管理状况。本文着眼于琉璃瓦釉的研究,开展了成分分析、釉烧温度分析,并探讨了成分变化的原因、以及成分变化对釉的性能和胎釉匹配性的影响。研究结果表明:雍正至宣统时期,釉中PbO含量呈降低的趋势、SiO2含量呈升高的趋势,特别是雍正至乾隆时期变化较为明显。这一变化可能与乾隆元年对雍正朝琉璃瓦釉料用铅量的核减有关。釉的成分变化导致釉的流动点温度升高,釉的热膨胀系数降低。乾隆时期出现了一批胎釉热膨胀系数匹配性较好的瓦件。

During the restoration of the Forbidden City these years, some glazed tiles with date inscriptions of the Qing dynasty were collected. Their raw materials and firing technologies show comtemporary ceramics technology and management system of the Qing court. Chemical compositions and melting temperature of the glazes were attained by ICP-AES. wet chemical analvsis and high temperature microscope. As to the chemical compositions of the glazes from Yongzheng period to Xuantong period, the PbO amount decreases while SiO2 amount increases. The trend is notable from Yongzheng period to Qianlong period. Accordding to historical documents, The government in Qianlong period decided to reduce amount of lead raw materials using on glazed tile production. The variation of PbO and SiO2 leads to raise the flowing point temperature and decrease in thermal expansion index.