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The results recently obtained by our group to get new thermoelectric materials belonging to the M-Pn-Ch ternary systems (M=Co, Fe, Ni; Pn=P, As, Sb, Ch=S, Se, Te) are here reported. We have considered the Ni-Sb-S ternary system, and some homogeneous samples of composition near to 1:1:1 were prepared employing a new and simple synthetic route, starting from pure elements. Scanning electronic microscopy, electron-probe microanalysis and X-ray powder diffraction were used to investigate the microstructure. The NiSbS lattice parameters were determined and the crystal structure was refined by Rietveld method. The crystal cell of NiSbS belongs to the P213 space group with a = 0.5931 nm. The thermal stability of the ternary compounds Ni-Sb-S was investigated by DSC technique. Electrical resistivity and thermoelectric power measurements at room temperature and at 77 K were performed on platelets obtained by cleavage of the bulk. [ABSTRACT FROM AUTHOR]

Abstract: Phase equilibria of the Au–In–Sn system have been investigated by Differential Scanning Calorimetry (DSC), metallographic examination, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) measurements. The 130 ∘C isothermal section of the phase diagram was studied. The ternary diagram shows six three-phase fields, and one ternary Au4In3Sn3 phase, which melts incongruently at 382 ∘C and shows a homogeneity range between 21 and about 30 at.% In, at constant Au/Sn ratio. The DSC results have been combined with microstructural observations and thermodynamic modelling [G. Cacciamani, G. Borzone, A. Watson, Thermodynamic modelling and assessment of the Au–In–Sn system, CALPHAD 33(1) (2009) 100–108] and seven invariant reactions have been identified. [Copyright &y& Elsevier]