Compounds and phase relations in the SrO–Fe 2O 3–CuO, SrO–Fe 2O 3–Gd 2O 3 and Gd 2O 3–Fe 2O 3–CuO ternary systems

Abstract

The subsolidus phase relations in the SrO–Fe 2O 3–CuO, SrO–Fe 2O 3–Gd 2O 3 and Gd 2O 3–Fe 2O 3–CuO systems have been investigated by the means of X-ray powder diffraction (XRD). All samples were synthesized in the air at 960 °C. There are nine binary compounds in the system SrO–Fe 2O 3–CuO. This system can be divided into twelve three-phase regions. A new ternary compound Sr 7Fe 17CuO 34 is identified. There are eight binary compounds and no ternary compound in the SrO–Fe 2O 3–Gd 2O 3 system. Nine three-phase regions lie in this system. In the Gd 2O 3–Fe 2O 3–CuO system, there are four binary compounds and no ternary compound. This system can be divided into five three-phase regions. The crystal structure of the binary compound SrGd 2O 4 was determined by powder XRD, this compound belongs to an orthorhombic structure with space group Pnma. The lattice parameters are a=10.1226(1) Å, b=3.4720(0) Å, c=12.0482(2) Å.