It is mainly used as additive element of Yttrium iron and Yttrium aluminium garnet and active material of phosphor. It is also used to make special alloys. It is used as an additive for magnetic materials and phosphors and for neutron activation analysis. It is mainly used for the preparation of new magnetic material yttrium iron garnet and solid laser material yttrium aluminium garnet. It can also be used as activator of phosphor and sensitizer of cathode material.