| On the base of the development of conductive ceramics, BaPbO3, a lower costs metal compound, was selected as the conductor phase of thick film resistors. For its excellent conductivity, it can replace precious noble metal and its oxides.In this paper, a new method based solid-phase reaction principle was put forward to prepare BaPb1-xBixO3 based thick film. The reaction process of BaCO3-Pb3O4, BaPbO3-Bi2O3 and BaPbO3-Bi2O3-Ag powders and the microstructure and electronic performance of thick film resistors were characterized by DSC-TG, XRD, OM and so on. The reaction mechanism, sintering mechanism and conductive theory were systematically discussed.BaPbO3 were prepared by Mechenical alloying (MA) and solid state reaction (SSR). It is found that BaPbO3 yield percentage was higher with increasing of milling time and appropriately more Pb3O4 in the base of Stoichiometric composition of BaPbO3. With the increase of temperature , Pb3O4 of the mixture of BaCO3- Pb3O4 decompose into PbO, then PbO and BaCO3 compound into BaPbO3. After milling 12h and sitering 6h at 700℃, pure BaPbO3 was prepared. Process of reaction of mixed BaPbO3-Bi2O3 and BaPbO3-Bi2O3-Ag powers were investigated. It is showed that BaPbO3-Bi2O3 and BaPbO3-Bi2O3-Ag powers of the sinteringproducts contents is of the relative stability at 700℃800℃. Ag can be stabilizing the structure of BaPb1-xBixO3 at high temperature.The reaction process of mixed BaPbO3-Bi2O3 and BaPbO3-Bi2O3-Ag powder were investigated. It is found that the productions of BaPbO3-Bi2O3 and BaPbO3-Bi2O3-Ag powder were stable at 700℃-800℃. Ag can make BaPb1-xBixO3 stable at high temperature, and prevent BaPb1-xBixO3 from decomposing.Effects of parameter x on the properties of BaPb1-xBixO3 were studied, and the result shows that, with the increase of x, TCR turned negative and electrical resistivity was higher. When the value of x is 0.5, the sintering activation energy is the lowest. The factors on the properties of BaPb1-xBixO3 based thick film were researched. It is showed that the square resistance and TCR negative of BaPb1-xBixO3 based thick films was higher with increase of content of Bi2O3 and thickness of fired film. Square resistance of BaPb1-xBixO3 based thick films was near-linear increased and TCR of BaPb1-xBixO3 based thick films was near-linear decreased with increase of content of Ag.The electric conduction model of BaPb1-xBixO3 based thick films was formed. BaPb1-xBixO3 based thick film is actually conductive with lead and bismuth oxide, the main factors on the properties of thick film is the electric resistance and contact resistance of conductive particulates; The electric conduction model of Ag- BaPb1-xBixO3 based thick film: The general structure of conductive network is constructed by conductance chain of Ag and is submerged into BaPb1-xBixO3 based conductive ceram.
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