New equilibrium phase in the Fe–Ge system obtained by mechanical alloying

A new equilibrium phase has been found in the Fe–Ge system. It has the composition Fe2Ge3, and decomposes at about 580°C due to a peritectoid reaction, giving FeGe (cubic modification) and FeGe2. The phase forms by a eutectoid reaction from FeGe2 at about 530°C; however, this transformation is kinetically inhibited. The Fe2Ge3 compound is likely to have a tetragonal lattice, structure type of Ru2Sn3, a=5.59 Å, c=8.92 Å.