烧结工艺对50％Mo-ZrO2金属陶瓷导电性能的影响

Influence of Sintering Process on Electrical Properties of 50%Mo-ZrO_2 Cermet

以氧化锆和钼粉为原料,在不同烧结工艺下制备了50%Mo-ZrO2金属陶瓷。采用扫描电镜和能谱仪分别分析了试样的微观结构和成分,用四电极法研究了试样高温电阻率。结果表明,增加烧结保温时间和提高烧结温度,可使试样烧结的更加致密,但试样的高温电阻率变化不大,800～1600℃该材料的电阻率与温度的关系为:κ=-0.41+0.006 T。试样的电阻率总体上随温度升高而增大,晶粒较大的试样电阻率在1150～1200℃出现峰值。

50%Mo-ZrO2 cermet was prepared by ZrO2 and Mo powder under different sintering processes. SEM and EDS were adopted to analyze the microstructure and chemical composition of the samples, respectively. High-temperature electrical resistivity of the samples was measured by four-probe methods. The results indicate that increasing sintering time and enhancing the sintering temperature can lead to samples more compact in structure, but the change of high-temperature electrical resistivity of the sample is not obvious, equation about electrical resistivity and temperature within the range of 800- 1600 ℃ is k =-0.41＋0.006T. The electrical resistivity generally increases with the increase of temperature, and a peak value of the electrical resistivity emerges between 1150 ℃ and 1200℃ in the sample with large grain size.