Magnetic and X-Ray Studies of Iron-Germanium System I Partial Diagram of Phase with B82 and Its Variant Type of Structure

The earlier diagram of β phase region is revised on the basis of x-ray and magnetic studies, and the existence of three phases β, η, κ is confirmed. The new β phase is homogeneous in a range from 32.8 to 40.0 at% Ge at 1050°C, η phase from 40.8 to 43.5 at% Ge at 800°C and κ phase has a narrow range of homogeneity at 43.5 at% Ge below about 500°C. Two phase region between β and η is very narrow. β Phase has a B8 2 (Ni 2 In) type of structure and is ferromagnetic. Alloy in the iron rich region of β phase is stable at high temperature and the quenched one precipitates a metastable phase with b. c. c. structure. η Phase is ferromagnetic and has a variant structure of B8 2 type. The structure of κ phase is still unknown and the magnetism is probably paramagnetic.