Properties of high density LaB6 cathode prepared by spark plasma solid phase sintering

High density LaB6 polycrystalline bulks were fabricated by spark plasma sintering(SPS) LaB6 powders prepared by boron carbide reduction method. The effects of sintering temperature and pressure on the phase formation, microstructure and properties of the sintered LaB6 bulks were studied systematically. The optimal technological parameters are sintering temperature of 1 650 ℃, sintering pressure of 50 MPa and holding time of 10 mins. It is shown that, the mechanical and emissive properties of the sintered LaB6 bulks are much better than that prepared by other methods. The relative density of the LaB6 sintered by SPS is up to 96.2%, and its vickers hardness reaches 1 720 kg/mm2. The highest bend strength is 203.2 MPa. The electron emitting density of the polycrystalline LaB6 sintered by SPS