The phase diagrams of the La-Ru and Nd-Ru systems have been investigated using differential thermal analysis, metallographic analysis, X-ray diffraction and electron microscopy. The ruthenium-rich side (80–100 at.% Ru) has not been studied owing to the high melting temperatures. The compounds R3Ru (Fe3C type), R5Ru2 (Mn5C2 type) and RRu2 (MgCu2 type) have been confirmed. Two new intermediate phases have been found: R7Ru3 which crystallizes with the Sr7Pt3 type and RRux, at about 38 at.% Ru, the structure of which should be related to the Y44Ru25 type. None of these phases show appreciable ranges of solid solubility. Additions of ruthenium to lanthanum and neodymium do not significantly affect their transition temperatures. The two phase diagrams appear to be nearly the same.
THE PHASE-DIAGRAMS OF THE LA-RU AND ND-RU SYSTEMS
CANEPA, FABIO MICHELE
1990-01-01
Abstract
The phase diagrams of the La-Ru and Nd-Ru systems have been investigated using differential thermal analysis, metallographic analysis, X-ray diffraction and electron microscopy. The ruthenium-rich side (80–100 at.% Ru) has not been studied owing to the high melting temperatures. The compounds R3Ru (Fe3C type), R5Ru2 (Mn5C2 type) and RRu2 (MgCu2 type) have been confirmed. Two new intermediate phases have been found: R7Ru3 which crystallizes with the Sr7Pt3 type and RRux, at about 38 at.% Ru, the structure of which should be related to the Y44Ru25 type. None of these phases show appreciable ranges of solid solubility. Additions of ruthenium to lanthanum and neodymium do not significantly affect their transition temperatures. The two phase diagrams appear to be nearly the same.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
