Si掺杂对Mn-Co-Ni系NTC热敏电阻电性能的影响

Eeffect of Si dopng on the electric properties of Mn-Co-Ni type NTC thermistors

采用传统陶瓷工艺制备了Mn1.05-xCo0.92Ni 0.03SixO4(0≤x≤0.05)系列NTC热敏电阻样品,借用XRD、SEM和电性能测试等手段,研究了Si掺杂量对样品相结构和电性能的影响。结果表明:当0≤x≤0.03时,样品为尖晶石立方相和四方相的固溶体,室温电阻率ρ25和B25/50值均随着Si掺杂量的增加而增加;当0.03<x≤0.05时,样品为尖晶石立方相,ρ25和B25/50值均随着Si掺杂量的增加而降低。当x=0.03时,在1 373 K烧结获得的样品电性能较好:ρ25=79 501Ω·cm,B25/50=4 142 K。

Mn1.05-xCo0.92Ni0.03SixO4（0≤x≤0.05） series NTC thermistor samples were prepared using the conventional ceramic technique. The effects of Si-doping amount on the phase structure and electric properties of the samples were studied using XRD, SEM and electric property measurements. The results show that in the range of 0≤x≤0.03, the spinel cubic phase and tetragonal phase co-existed as solid solution in the samples, and the resistivity at room temperature P25 and B25/50 value of the sample increased with increasing Si-doping amount. When 0.03〈x≤0.05, the tetragonal phase was absence and only spinel cubic phase existed in the samples, and the B25/50 value and P25 of the sample decreased with increasing Si-doping amount. The obtained sample with x = 0.03 sintered at 1 373 K show optimal electric properties with ρ25 of79 501 Ω·cm, and B25/50 value of 4 142 K.