Controlled thermistor effect in the system CuxNi1–x–yCo2yMn2–yO4

The problem of selection guidelines for oxide semiconducting ceramics with controlled thermistor effect, prepared on the basis of complex CuxNi1–x–yCo2yMn2–yO4 (0.1⩽x⩽0.8; 0.1⩽y⩽0.9–x) chemical system and restricted by CuMn2O4, MnCo2O4 and NiMn2O4 spinel-structured compounds, is discussed. It is shown that the developed ceramic thermistors with a wide range of predetermined exploitation parameters (rated resistance from 2 to 21,500 Ω, material-specific constant B of NTC thermistor from 2435 to 3365 K), as well as a high level of reliability can be obtained using the proper methods of technological, compositional and design modifications. The attempt to establish a general relationships between chemical composition, technological features of sintering and electrical properties for single-phase ceramics is made, using the method of simplex matrices of the 4-fold D-optimum plan.