Effect of sintering temperature on morphology and arc erosion properties of La-Ni-O ceramic and its composites

Ceramic LaNiO3 samples were prepared by solid state reaction method at different sintering temperatures. It was found that the resultant was not ABO3 perovskite single phase but dual phase La2NiO4 and NiO, and the percentage of the two phases varied with sintering temperature. Ceramics sintered at 1400 °C were well crystallized and the phase ratio of La2NiO4 was the maximum. The surface morphology observed by scanning electron microscopy (SEM) indicated that the grains of the ceramics sintered at 1400 °C were uniform and compact, which were in agreement with the properties of high density and low electrical resistivity of the samples. X-ray diffraction (XRD) patterns of ceramics before and after arc erosion indicated their high structural stability, which resulted in the good arc erosion resistance properties for silver-based electrical contact materials. The contact materials prepared with the ceramic sintered at 1400 °C exhibited better mass transition and arc erosion resisting properties.