Structural and Electromagnetic Properties of Lithium Ferrite Manufactured by Extrusion Printing

The structure and electromagnetic properties of a lithium ferrite, Li_0.5Fe_2.5O₄, fabricated by an additive manufacturing process based on extrusion printing of ferrite samples with a binder substance followed by hightemperature sintering are studied. A preliminary ferrite-powder synthesis is carried out by the solid-phase method using iron oxide and lithium carbonate. The ferrite paste for printing is prepared using a binder based on ethyl cellulose and terpineol. The samples measuring 100 and 500 μm are fabricated by extrusion in a Voltera V-one 3D printer. The samples are sintered in a laboratory furnace at 1100°C. The microstructure and properties of the resulting ferrites depend on the printed layer thickness. The samples are characterized by a relative density of 72 and 76%, a specific saturation magnetization of 50 and 62 emu/g, a Curie temperature of 625 and 630°C, and a specific electric resistivity of 1.1·10¹⁰ and 1.6·10⁹ Ω·cm for the 100 and 500 μm-thick samples, respectively.