Microstructure and electrical properties of Sm2O3-doped ZnO-based linear resistance ceramics
ZnO-based linear resistance ceramics were synthesized from ZnO–MgO–NiO–Al2O3–SiO2–Sm2O3 at 1320 °C for 3 h by the conventional ceramics method. The microstructure and electrical properties of the linear resistance ceramics have been systematically investigated in detail. The experimental result indicates that appropriate amounts of Sm2O3 addition can obviously improve the resistance temperature coefficient of ZnO-based linear resistance ceramics compared with the Sm2O3-free samples. The samples with the Sm2O3 content of 0.5 mol% exhibit excellent electrical properties with the resistivity of 209.8 Ω cm and the resistance temperature coefficient of 2.38 × 10−4/°C, which is improved by 46 and 92 %, respectively. Moreover, the nonlinear coefficient of voltage decreases to 1.15, decreased by 4.30 % and the relative density reaches to 96.43 %, increased by 4.91 %.
KeywordsSm2O3 Nonlinear Coefficient Negative Temperature Coefficient ZnAl2O4 Positive Temperature Coefficient
This work was supported by the Key Project of Chinese Ministry of Education (No. 210218), Scientific and Technological Project of Wenzhou (H20100079, H20100087), and the Graduate Innovation Fund of Shaanxi University of Science and Technology.
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