北京龙泉务窑辽金代黑瓷的制作工艺和显微结构研究

STUDY ON MICROSTRUCTURE AND TECHNOLOGY OF BLACK PORCELAIN OF BEIJING LONG QUAN WU KILN IN L IAO AND JIN DYNASTIES

龙泉务窑黑瓷粗、细胎用原料分别与白瓷粗、细胎相同，故可以认为当时该窑在制作瓷坯时是不分黑瓷白瓷的，只是涂釉不同。样品外观分为茶叶末釉、酱色釉、油滴黑釉和普通黑色釉，它们釉的含铁量在３ ．３ － ７ ．８ ％ 。釉滴黑釉组成特征是含高硅（７４ ．１ ％ ） 、低铝（１２ ．１ ％ ） 和低铁（３ ．３ ％ ） ，其釉属钙碱釉，釉较厚，釉表面有磁铁矿微晶，使外观呈银色小油滴。茶叶末釉属钙质釉，釉中生长较多的钙长石和普通辉石晶体，还有残留石英和磁铁矿结晶，所以形成茶叶末釉的外观。酱色釉是由部分含铁量较高（６ ．６ － ７ ．８ ％ ） ，钙镁氧化物含量较低的黑釉在较高的烧成温度和较强的氧化气氛下烧成，釉面生成赤铁矿晶体层，故外观表面呈酱红色，面下仍为黑色。样品烧成温度１２００ － １３００ ℃。

Theraw materialsused offine and coarse body ofthe samples were the same asthose of white porcelain ofthe same kiln respectively.Theappearanceofglazesamplesisthetea dustglaze,darkreddish brown glaze,oil-spotglazeand black glaze.The Fe2O3contentsofthese glazeare3 .3 -7 .8 % .Thecompositioncharacteristicsofan oil- spotglazeare high SiO2(74.1% ) ,low Al2O3(12 .1% )and Fe2O3(3.3 % ).Theoil-spotglazeis Ca- alk- glazeandthick(thickness:0.45m m).Thereis magnetitecrystal liteon the glaze surface.Sothe appearance ofoil- spotissilvery.Thetea dust glazeis Ca- glaze.Inthe glaze,thereare more augite and anorthitecrystalline,residualquartzand magnetite.Sothe appearance oftea dustglaze wasformed.Athinlayer ofhematitecrys talline wasformedonthesurfaceofblack glazecontaining high Fe2O3(6 .6 - 7.8 % )andlow CaOand MgObecausethesamples were fired atthehighfiringtemperature(about1300℃) andstrong oxidizing atmosphere.Sotheappearanceofthesamplesappearsindarkreddish brown color.Thefiringtemperature ofthe black porcelain samplesisabout1200 -1300℃.