The phase diagram of the Yb-Si system

The phase diagram of the Yb-Si system has been studied up to about 80 at.% Si by means of multitechnique investigations: differential thermal analysis (DTA), X-ray diffraction (XRD), optical microscopy (LOM), electron probe microanalysis (EMPA) and complemented with tensimetric measurements using the Knudsen effusion-mass spectrometry (KE-MS) and Knudsen effusion-weight loss (KE-WL) techniques. Besides the four already known intermediate phases: Yb5Si3 (Mn5Si3-type), YbSi (CrB-type), Yb3Si5 (Th3Pd5-type) and YbSi2-x (AlB2-type), two new compounds have been found and completely characterized: Yb5Si4 (Sm5Ge4-type) and Yb3Si4 (Ho,Si.-type). Two eutectics occur in this system: at less than 1 at.% Si (815 degreesC) and at about 82 at.% Si (1145 degreesC). (C) 2002 Elsevier Science B.V. All rights reserved.