Preparation of Ytterbium Iron Garnet Powder by Homogeneous Precipitation Method and Its Sintering

Abstract

Yb₂O₃-Fe₂O₃ powders were prepared from ytterbium and iron chloride solutions by a homogeneous precipitation method where urea was used as precipitant. The precipitation process was carried out stepwise. At first the iron hydroxide was precipitated and then the ytterbium hydroxide was formed. In the firing process of precipitated powder the ytterbium orthoferrite was formed initially from the iron oxide and ytterbium oxide, and monophasic ytterbium iron garnet was obtained above 1200°C. The reactivity and sinterability of the powder obtained by the homogeneous precipitation method were better than that of oxide mixture. The ytterbium iron garnet contained up to 0.1-0.2mol% iron oxide in excess of the stoichiometric composition.