Preparation and properties of 4.25Cu-0.75Ni/NiFe₂O₄cermet

来源期刊：中南大学学报(英文版)2005年第3期

论文作者：李劼 张刚 赖延清 田忠良 秦庆伟

文章页码：284 - 289

Key words：NiFe₂O₄; cermet; preparation; property; inert anode

Abstract: 4.25Cu-0.75Ni/ NiFe₂O₄ cermets were prepared by doping NiFe₂O₄ ceramic matrix with the mixed powders of Cu and Ni or Cu-Ni alloy powder as the electrical conducting metallic elements. The effects of technological parameters, such as the adding modes of metallic elements, the ball milling time, the sintering time and the sintering temperature, on the relative density and resistivity of the cermets were studied. The results show that the resistivity of 4.25Cu-0.75Ni/ NiFe₂O₄cermets decreases with increasing temperature, and has a turning point at 590℃, which is similar to that of NiFe₂O₄ceramic. The sintering temperature and adding modes of metallic elements have a great influence on the properties of 4.25Cu-0.75Ni/ NiFe₂O₄ cermets. When the sintering temperature increases from 1 200℃to 1 300℃, the relative density increases from 89.86% to 95.33%, and the resistivity at 960℃decreases from 0.11Ω·cm to 0.03Ω·cm, respectively. When the metallic elements are added with the mixed powders of Cu and Ni, the cermets of finely and uniformly dispersed metallic phase, high density and electric conductivity are obtained. The relative density and resistivity at 960℃are 90.23% and 0.04Ω·cm respectively for the cermet samples sintered at 1 200℃for 2 h, which are both better than those of the cermets prepared under the same technique conditions but with the metallic elements added as 85Cu-15Ni alloy powders.