| High efficiency infrared radiation ceramics were prepared and studied in this investigation, with three systems of xFe2O3-(80-x)MnO2-10Co2O3-10CuO, xFe2O3- (80-x)MnO2-10Co2O3-10CuO-yNi2O3-(60-y) Cr2O3 and xFe2O3-(80-x)MnO2-10Co2O3 -10CuO-t TiO2. And the processing conditions were controlled to be different. In order to study the relationship between the properties and processing, the emissivity of the samples prepared was evaluated by different methods, and the chemical environment of the inner ions as well as the microstructure of the material was tested by modern testing methods such as XRD, SEM, FT-IR and XPS. The main results were shown as follow.1. Fe-Mn-Co-Cu system was doped by various transitional metal oxides, high efficiency radiation materials with emissivity of 0.93~0.94 on the whole infrared band were obtained.2. Sintering under deoxidizing atmosphere as well as cooled rapidly in the air was benefit to improve the emissivity on shortwave band, but slightly reduce that of long wave band.3. When the material was synthesized mainly from Fe2O3 and MnO2, spinel crystal structure would be gained. And as the increasing of Fe2O3, the crystal grain would grow rapidly.4. When the ion of Cr doped into the Fe-Mn-Co-Cu system, with its high Octahedron Space Preference Energy (OSPE), it entered the crystal lattice of spinel effectively. While doped by Ni with the weight more than 40%, because of its relative low OSPE, Ni didn't enter the crystal lattice completely, thus emissivity reduced.5. When the Fe-Mn-Co-Co system was doped by TiO2, ion of Ti entered the crystal lattice and remain the spinel structure, on one hand, it makes Fe and Mn took relative lower chemical valence, and on the other hand, it lead to deformation to the crystal lattice. All above were benefits to improve the radiation property of the material. But when the amount of TiO2 doped in exceeded 40% in weight, Mn was excluded out of the spinel crystal lattice, and thus made the emissivity reduced.
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