Fabrication and characterization of high density LaB6 polycrystalline with (100) preferred orientation

High density lanthanum hexaboride (LaB6) polycrystalline with (100) preferred orientation was prepared by spark plasma sintering (SPS) using LaB6 nanocubes as raw materials in this work. Microstructure and thermionic electron emission property of LaB6 polycrystalline were investigated detailedly. The results show that the LaB6 polycrystalline had a relative density of 95.8%, and there was a (100) preferred orientation on its surface normal to SPS pressing direction. The work function of LaB6 polycrystalline normal surface was only 2.73 eV, which was almost close to the theoretical work function of LaB6 (100) single crystal surface. The reasons for preferential orientation of LaB6 polycrystalline were analyzed.