Phase equilibria in the Er–Al–Si system at 873 K

The isothermal cross-section of the phase diagram of the system Er–Al–Si at 873 K was constructed based on X-ray powder diffraction. The existence of the compounds Er2Al3Si2 (Y 2Al3Si2-type structure), ErAlSi (YAlGe), Er2AlSi2 (W2CoB2), and Er2Al1.5Si1.5 (Mo2FeB2) were confirmed and the formation of three new ternary alumosilicides was established: ErAl2.8Si0.2 (HT-PuAl3,hP24,P63/mmc,a=0.60295(4),c=1.42308(9) nm),∼Er5Al6Si4 (unknown structure), and Er6Al3Si (Tb6Al3Si,tI80,I4/mcm,a=1.1436(2),c=1.4854(2) nm).