Preparation and electrical properties of TiC nanowires/Mo-Al₂O₃ cermet

Mo-Al₂O₃ cermet has the advantages of good thermal shock stability, high temperature resistance and low resistance, and has been used as the core component in the process of ultra high voltage direct current (UHVDC) transportation. However, due to the poor controllability of resistivity, high seepage threshold and low mechanical strength, its wide application in UHVDC transportation is seriously restricted. TiC_NW/Mo-Al₂O₃ ceramic composites with bridge structure were prepared by using titanium carbide nanowires (TiC_NW). The bridge structure constructed between TiC_NW, Mo and Al₂O₃ was studied, and the influence of the bridge structure on the electrical and mechanical properties of cermets was studied. The percolation threshold is reduced on the basis of stable resistivity of cermets. When the TiC_NW content is 13wt%, the percolation threshold of Mo-Al₂O₃ cermet is reduced to 10wt%. When the TiC_NW and Mo contents are 8wt% and 30wt%, respectively, the flexural strength and hardness of cermet can reach 95 MPa and 1283 kg/mm², respectively, and the cermet bridging structure is observed. The research results are of great significance for the preparation of high-performance Mo-Al₂O₃ cermets.