Lanthanum hexaboride, lanthanum boride for short, molecular formula: LaB6, purple powder, hardly soluble in water and hydrochloric acid, is widely used and has been successfully used in more than 20 military and high-tech fields such as radar aerospace, electronic industry, instruments, medical equipment, home appliances metallurgy, and environmental protection. Its series of products mainly include three kinds of powder, multi-crystal, and single crystal. In particular, lanthanide hexaboride single crystal, is the best material for making a high-power electronic tube, magnetron, electron beam, ion beam, or accelerator cathode.