Preparation And Characteristics Of High-temperature Infrared Electrothermal Films

Impurity Sno2 electrothermal films have been prepared by means of chemical depositing technique on ceramic substrate.The effects of reaction temperature, annealing techniques, solution component and doping concentration, on room resistance values, resistance-temperature characteristics and infrared radiation characteristics of the electrothermal films have been studied. The result shows that: The resistance of films are changed with substrate temperature and annealing conditions (annealing temperature and annealing time). With the increasing of substrate temperature, resistance of films decrease. Optimum reaction temperature is 400?-600?. Sb-doped can improve temperature resistance of electrothermal films,resistance stability and temperature coefficient of resistance, optimum doping content for Sb-doped is 1.5%. Lowly Sb-doped films show negative temperature characteristics(NTC), contrarily, highly Sb-doped films show positive temperature characteristics(PTC). The films of PTC have characteristics of self-limiting electric current and self-limiting temperature. In addition, SnO2 electrothermal films doped Cr2O3, MnO2, Ni2O3 ,etc. have high spectral emissivity and high radiation efficiency.