Tetragonal phase in Al-rich region of U-Fe-Al system

A new ternary aluminide U2FeAl20 with the approximate composition Al-4.2 at% Fe-8.5 at% U was observed in the Al-rich corner of the U-Al-Fe system. Transmission electron microscopy and electron microdiffraction technique were used for characterization of the structure of this phase. It has a tetragonal unit cell with the parameters a = 12.4 Å and c = 10.3 Å and can be described by the space group I4¯2m.