Among the five famous kilns of the Song Dynasty,Ding kiln is the only one famous for white porcelain production,whose superb technique processes such as engraved designs and original upside down firing,had a profound influence on many kilns home and abroad.Nondestructive Energy Dispersive X-Ray Fluorescence (EDXRF) analysis method was applied to analyze the chemical composition and the recipe of the Ding white porcelain from the Tang Dynasty (618-907A.D.) to the Jin Dynasty (1115-1234A.D.).The valence state of Fe in the glaze of Ding white porcelains was analyzed with X-Ray Absorption Fine Structure (XAFS) for the first time while discussing the firing technique.It was found that the bodies of Ding white porcelains were characterized as "high alumina and low silicon" of typical northern porcelains,and raw mineral materials rich in CaO was intentionally added to the bodies' recipe in order to promote the sintering of the body.TiO2 in the bodies was generally introduced by impurity of kaoline.The glazes of Ding white porcelains were characterized as "high calcium and high magnesium",which generally belonged to Calcium magnesium glaze or Calcium magnesium alkaline glaze.Its recipe should contained a certain content of dolomite or talc.The increasing content of K2O in theglazes reflected the transition from Calcium magnesium glaze to Calcium magnesium alkaline glaze.In addition,wood ash and kaoline should be added to the recipe of glazes according to the chemical composition characteristics of Al2O3,MnO and P2O5.The XAFS results showed that the Fe3+ proportion in the Ding white glaze of the Late Tang Dynasty and the Five Dynasties was the highest,while that of the Jin Dynasty taked the second place,followed by that of the Song Dynasty.So it implied that Ding white porcelains of successive dynasties were fired in a reducing atmosphere.The yellowish colour of Ding white porcelain in the Song and Jin Dynasties was probably caused by Fe-S compound produced in the firing process by the interaction of glaze and sulfur enriched in thefuel coal.%定窑是我国宋代五大名窑中唯一以生产白瓷而闻名于世的窑厂,其高超的刻印花纹技术及首创的支圈覆烧工艺,对国内外许多窑场产生了深远的影响.采用(energy dispersive X-ray fluorescence,EDXRF)探索了历代定窑白瓷的组成配方,并采用X射线吸收精细结构(XAFS)法分析了瓷釉中Fe元素的价态,以探讨定窑白瓷的相关烧制工艺.研究发现,定窑白瓷瓷胎具有典型北方瓷器"高铝低硅"的特征,并在瓷胎中特意添加了富含CaO的矿物原料,对瓷胎的烧结有一定的促进作用.瓷胎中的TiO2应主要是高岭土原料中的杂质.定窑白瓷瓷釉具有"高钙高镁"特征,基本属于钙镁釉或钙镁碱釉.其瓷釉配方中应含有一定量的白云石或滑石.瓷釉中K2O的含量逐步增加,反映了定窑瓷釉由钙镁釉向钙碱釉发展演变的过程.此外,根据瓷釉中的Al2O3,MnO和P2O5等含量的特征,可以推测釉料配方中应添加了草木灰和高岭土.由XAFS分析结果可知,晚唐五代时期定窑白瓷釉中Fe3+比例最高,金代次之,宋代最低,不同时期定窑白瓷皆是在还原气氛中烧成.宋金时期定窑白瓷白中泛黄可能由于燃料煤中富含的硫在燃烧过程中与瓷釉反应,生成Fe-S化合物所致.
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