Phase relations and stabilities at 900°C in the U–Fe–Si ternary system

Determination of the crystallographic structure of the new U6Fe5Al8Si9 compound

“…X-ray powder diffraction taken from the sample revealed the presence of U 6 Fe 5 Al 8 Si 9 compound as a dominant phase (approximately 86 wt%), and impurities of U 2 Fe 3 Si 5 [28], UFe 2 Si 2 [29] and UFe 4 Al 8 [4] phases.…”

Isothermal section of the ternary phase diagram U–Fe–Ge at 900 °C and its new intermetallic phases

“…The U-Fe-Si has nine reported stable compounds and four intermediate phases at 900ºC [11]. For the U-Fe-Ga [13] and U-Fe-Al [10] systems, the degree of substitution between iron and gallium or aluminium is the outstanding aspect and the consequence is the high stability of six homogeneity ranges, which can be found in each one of the respective isothermal sections. In all these systems, the most stable homogeneity ranges are of binary types (such as ThMn 12 or Th 2 Ni 17 ), which do not exist in the binary diagram U-Fe but can be stabilized by the addition of the p element.…”

“…Isothermal sections for uranium systems of the type U-Fe-X were already reported for X = B [8], Al [9], Si [10], Sn [11], and Ga [12]. Preliminary results on the isothermal section of the UFe-Ge at 900ºC were reported [13], the systematic study of this system revealing a rich variety of new compounds.…”

Determination of the crystallographic and electronic structure of U2Fe3Si5 compound

“…This compound was first described by Hickey et al [8] as crystallizing in monoclinic structure belonging to space group C2/c with the unit cell parameters a = 10.848Å b = 11.476Å, c = 5.518Å and ˇ = 119.38 • . Later Berthebaud et al [9] who investigated the U-Fe-Si phase diagram at 900 • , have reported about existence of the U 2 Fe 3 Si 5 phase with almost the same "a", "b" and "ˇ" parameters, but with the smaller "c" parameter (5.163Å).…”