通过XRD、SEM分析和变温、变频条件下的lgρ-t测量,对Co-Mn-Ni-O2系热敏材料的lgρ-t特性与频率f的关系进行了研究。结果表明:CoMn1.4Ni0.6O4尖晶石型氧化物热敏电阻材料的阻温特性在0.1~1MHz和–70~+100℃,发生了PTC向NTC的转变,且转变点的温度(–70~–10℃)和f(0.1~1MHz)与材料电阻率ρ有关。根据电导率σ和载流子浓度n、载流子迁移率μ之间的关系,用小极子跳跃导电理论对上述现象作了解释。 The relationship between lgρ-t characteristics and frequency f of Co-Mn-Ni-O2 thermal-sensitive materials was investigated by XRD, SEM and lgρ-t measurement under variable temperature and frequency. The results show that the resistance temperature characteristic of CoMn1.4Ni0.6O4 spinel oxide thermistor material changes from PTC to NTC at 0.1 ~ 1MHz and -70 ~ + 100 ℃, and the temperature at the transition point (-70 ~ -10 ℃) and f (0.1 ~ 1MHz) and the material resistivity ρ. According to the relationship between conductivity σ and carrier concentration n and carrier mobility μ, the above phenomenon is explained by the theory of small-pole jump conduction.