The Study Of Preparation Technology On The Glaze Tiles From Poyang Huai Palace In Ming Ynasty

Po Yang Huai Palace,excavated in 2012,is one of the important Fanwang Palaces in Ming Dynasty,which unearthed a batch of green glazed tiles that have particular shapes and elegant glaze color.They provide valuable data to reveal the technology of Ming Dynasty building materials.The article based on different types of classical glazed tiles from Huai Palace relics as the research object,used EDXRF,SEM,and Thermal Dilatometer etc,combinated literature data to analyze the information of chemical composition of the body,mask clay and glaze、microscopic structure 、 phase composition and Physical Property,discuss the Preparation Technology of Huai Palace glazed tiles and the reason for peeling off of some samples.The research results show that the materials of blank making were used high aluminous clay.The mask clay was,on the basis of materials of blank making,added a certain amount of high potassium china stone raw,then by operating technological process of more fine grinding、elutriation、sieving and iron removal.The glaze was maxed of Lead powder、Mayashi、and copper powder by a certain proportion.The forming method of billet included two kinds:plate tile and semi-cylindrical are often made of round tile forming way,eaves tiles and drip tiles are often adopt mold forming.Glazing technology is: plate tile、semi-cylindrical such big component are often used poured glazing process,eaves tiles and drip tiles are may used leaching glaze process like other areas.In addition,Huai Palace glaze tiles were all adopt secondary firing technology,the firing temperature of body almost was above 1000 ℃,the firing temperature of glaze was between 820℃-970℃,firing atmosphere were both reducing atmosphere and oxidizing atmosphere.By the microstructure,it found that the main reason of glaze peeling is due to the thinner mask clay,because a certain thickness mask clay can increase the smooth degree on the surface of the body、reduce the rate of body surface and the spread loss from glaze to body in the process of product firing from glaze to billet.These reasons make thin glaze technology also can assure the surface of glaze was smoothly and lightly.Only when mask clay reaches about 500 μm will it make the best effect..Meanwhile,the thinner glaze laying within greater compressive stress,the greater change of the composition in firing process.So it can easy make the expansivity of body and glaze more closer,also the bond of body and glaze better.