Phase equilibria of the Dy–Al–Si system at 500 °C

• DOI: 10.1007/s10973-012-2196-7
• Publication Date: 2012-01-21T04:49:15Z
• Authors: Anna Maria Cardinale; Daniele Macciò; Adriana Saccone
• Keywords: Isothermal process; Differential thermal analysis; Powder Diffraction; Ternary compound

The isothermal section at 500 C of the Dy-Al- Si system was studied in the whole concentration range. The alloys were characterized by X-ray powder diffraction, scanning electron microscopy and electron micro-probe analysis. A few samples were analysed by differential ther- mal analysis. The following intermetallic compounds, some of them showing variable composition, were found: DyAl2Si2 (s1), hP5-CaAl2O2 structure type, Dy2Al3Si2 (s2) mS14-Y2Al3Si2 structure type, Dy2Al1?xSi2-x (s3), 0 B x B 0.25, oI10-W2CoB2 structure type and Dy6Al3Si (s4), tI80-Tb6Al3Si structure type. A number of binary pha- ses dissolve the third element forming ternary solid solu- tions: Dy(Al1-xSix)3 ,0 B x B 0.5, hP16-Ni3Ti structure type, Dy(AlxSi1-x)2 ,0 B x B 0.1, oI12-GdSi2 structure type, Dy(AlxSi1-x)1.67 ,0 B x B 0.2, oI12-GdSi2 structure type, DyAlxSi1-x ,0 B x B 0.2, oC8-CrB, and Dy5(AlxSi1-x)3, 0 B x B0.3, hP16-Mn5Si3 structure type. The melting point of Dy6Al3Si was determined.