Electrical Characterisation of Ni0.5Co0.3Cr0.2Mn2O4 Thermistors

Yıl 2017, Cilt: 13 Sayı: 2, 401 - 405, 11.05.2017

Berat Yüksel Price

https://doi.org/10.18466/cbayarfbe.308508

Öz

Negative
temperature coefficient (NTC) thermistors are ceramic semiconductors derived
from metal oxides such as Mn, Ni, Co, Cu, Cr, Fe etc. The electrical resistance
of NTC thermistors decrease with increasing temperature. In industrial
applications, the desired material constant (B) of NTC thermistors is in the
range of 2000 to 5000 K and the sensitivity coefficient (α) is in the range of
(-2.2) to (-5.5) %/K. The electrical properties of NTC thermistors can be
changed significantly by the type and molar ratio of metal oxide additions as
well as the selected process parameters during manufacturing of samples. In this study, the
effect of Cr₂O₃ addition on the electrical properties of Mn-Ni-Co-O
NTC
thermistors sintered at 1100 ^oC for 5 hours was investigated. The
electrical resistance was measured in a temperature programmable furnace
between 25 and 85^oC in steps of 0.1^oC. The material
constant “B”, the activation energy “E_a” and the sensitivity
coefficient “α” values were calculated. The aging behaviour of Mn–Ni–Co–Cr-O NTC
ceramics was also investigated by electrical resistivity measurement after
accelerated aging.

Anahtar Kelimeler

Aging, Chromium (III) oxide, electrical properties, NTC thermistor, sintering.

Kaynakça

• Park, K.; Han, I. H. Effect of Cr2O3 addition on the microstructure and electrical properties of Mn-Ni-Co oxides NTC thermistors. J. Electroceram. 2006; 17, 1069-1073.