Kinetics of garnet formation in In3+-substituted systems

Abstract Kinetics of solid-state reactions were investigated in Fe 2 O 3 –Y 2 O 3 –In 2 O 3 system from 700 to 1400°C by X-ray and by DTG/M/ methods. Mutual diffusion of iron and indium ions into each others oxide lattices was the first interaction, resulting in a gradual expansion or contraction of the two oxide lattices, respectively. On increasing the temperature the Y 2 O 3 reacted with the indium-containing Fe 2 O 3 and formed garnet through orthoferrite intermediates with a continuous incorporation of the indium below 1200°C. Significant differences appeared in the feature of the solid-state reactions above 1200°C depending on the stoichiometry because of the stabilizing effect of the iron ion diffusion in the In 2 O 3 lattice.