The 673 K isothermal section of the La–Ni–Sn ternary system

Abstract

The phase relationships in the La–Ni–Sn ternary system at 673 K have been investigated by means of X-ray powder diffraction (XRD), differential thermal analysis (DTA), scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). Most of this ternary system was studied at 673 K. At this temperature, a new ternary compound whose atomic ratio is close to La/Ni/Sn=1:1:3 has been found. The existences of 15 binary compounds La 7Ni 3, LaNi, La 2Ni 3, La 7Ni 16, LaNi 3, La 2Ni 7, LaNi 5, Ni 3Sn, Ni 3Sn 2, Ni 3Sn 4, La 5Sn 3, La 5Sn 4, LaSn, La 3Sn 5, LaSn 3 and seven other ternary compounds LaNi 5Sn, LaNi 4Sn 2, LaNi 2Sn 2, La 3Ni 2Sn 6, La 3Ni 2Sn 7, La 3Ni 8Sn 16, LaNiSn have been confirmed too. There are 31 three-phase regions in the 673 K isothermal section. Due to the lower melting point of Sn (about 504 K), a small part of the ternary system that lies in the Sn-rich part was studied at 483 K.