Study On Faience Simulation And Lead-Barium Glass Of The Ancient China During The Period Form Warring States To Qin Ang Han Dynasties

Faience is honored as an early stage in glass development by some scholars. Among these, the purple and blue faiences octagonal sticks during Warring state to Western Han dynasty are most remarkable duing to their unique lead barium composition and special weathering morphology. In this paper, the simulation experiments were conducted strating from the main color agent Chinese purple (Chinese Purple, BaCuSi2O6) and Chinese blue (Chinese Blue, BaCuSi4O10), then the simulation forming experiments of faience were taken place in the laboratory condition, finally the simulated product which was similar with the ancient sample have been obtained. The main work is as follows:1. Chinese purple and Chinese blue pigments have been synthesized with different synthesis methods, sources of barium and lead the catalyst. By XRD analysis and microscopic research of product, it was concluded that the high temperature solid phase method was more suitable as a response simulation experiment method, and BaCO3barium source was more likely to be used under laboratory conditions to obtain the pure product. By SEM, TG, DTG and XRD studies, it was concluded that compared with PbO and PbS, PbCO3can effectively reduce the synthesis reaction temperature. Within the range of the600-700℃, PbCO3can catalyze BaCO3decomposition, hence to create more pure Chinese purple pigment.2. Two seriously weathered purple-blue faience samples have been conducted the SEM+EDX and Raman test respectively, the same result of the phase analysis was obtained by different test methods, namely the main components of the outer crust were SiO2, PbCO3, A12O3and barium salt (BaCO3or BaSO4), and internal weathering part were mainly contained Chinese purple and some baric silicates.3. The molding process simulation experiment of the Warring States period some faience product was taken under laboratory condition including three bule beads with different shapes. By the XRF analysis, the chemical compositions of ancient blue-purple faience products were obtain for the simulated experimental formula. After the shape and microstructure comparation of the hand-molding simulation product and the ancient samples, it can be determine that the simulated samples were quite similar with the ancient samples.4. In the molding simulation experiment of blue-purple faience octagonal sticks, the relationship between lead content and firing temperature, sintering times, forming pressure and molding method were studied. By comparison the density and porosity with the simulation and the ancient samples, findings were as follows:a serious impact on the lead content of the finished state of faience products, for common high lead content faience products, the maximum reaction temperature generally did not exceed950℃(lead salt content of>35wt%). The simulation sample can be obtained by undergoing an secondary sintering process, pressure forming under a1500-2000psi (10.34-13.79MPa) pressure, then goting through a manual polishing, eventually could gain the ancient samples is very similar to the simulation.5. Two ancient green Chinese Pb-Ba glass (Qin and Han dynasties) were studied with Raman microspectroscopy and SEM-EDX. Some needlelike silicates was found in the samples and inferred as BaSiO3, BaSi2O5and PbSiO3according to the results of EDX analysis. Then BaSiO3, BaSi2O5,PbSiO3were synthetized in laboratory in order to obtain their Raman spectra. Through comparative study, the needlelike silicates in the ancient Pb-Ba glass samples were proved to be BaSiO3, PbSiO3and Al2O3.