| In this paper, the samples of ZrO2/MoSi2 hybrid electrical materials are fabricated by mould-pressing and extrusion-pressing methods, the mechanical properties ,electrical properties, thermal properties of samples are tested according to GB standard. The SEM(Scanning Electron Microscope), Metallographical Polariscope ,XRD(X-ray diffraction) are used to analyze the fracture morphology , phase composition in details. The effects of ZrO2 contents, sintering time on microstructure and properties of Hybrid Electrical materials are studiedWe found that the density and densification tend to increase firstly then decrease and the void ratio changes reversely with the increasing of ZrO2 contents . The reason of densification decreasing is that during the sintering process because of the big particle size and lower contents of ZrO2 the voids are prior to form in big size. When ZrO2. is in large volume , ZrO2 dispersed and more small voids formed the densification of hybrid materials will decrease slowly .And because of ZrO2 is insulated in low temperature so the resistivity of hybrid materials will be extremely increased with the adding or ZrO2. At the same time , the resistivity of hybrid materials is correlated to its densification. The fracture type of hybrid materials is mainly inter-granular . With the increasing of ZrO2 volume contents, the inter-granular-will be partly replaced by intra-granular fracture. It not means that the properties, especially the mechanical properties of materials will decrease but means that the intra-granular fracture is the results in higher loads. Therefore, the adding of ZrO2 is advantage to the improvement of materials properties. And with the increasing of the sintering time, the effects will be strengthened . ZrO2 particles play an important role as hard-phase to strengthen the materials . The increasing of sintering time also can greatly improve the properties of the hybrid materials. |
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