The effect of cation composition on the electrical properties and aging ofMn-Co-Ni thermistors

The aim of this paper is to investigate the effects of nickel-containing co mpositions on the electrical properties and aging of NTC thermistors with t he composition (NixMnyCoz)O-4 (where x + y + z = 3) at room temperature. Th e results indicate that the electrical resistivities decrease as the nickel content increases, but reach a minimum value and then increase. The result s five months after manufacture time show also that as the content of nicke l increases the samples are more stable. The effects of nickel on the mater ial constants (B, A) and various other electrical parameters are also repor ted. (C) 2000 Elsevier Science Ltd and Techna S.r.l. All rights reserved.