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Abstract: The thermal expansion and stability of predominantly single-phase Ti2SC powders in argon and air was investigated by Rietveld analysis of synchrotron X–ray diffraction spectra. When the sample was heated in an Ar atmosphere, it started to dissociate into TiS2 (see footnote 1) at ≈400°C. At 8.5 (5)×10−6 °C−1 and 8.8 (2)×10−6 °C−1 the thermal expansion coefficients along the a and c-directions, respectively, are quite similar. The volumetric thermal expansion is 25.2 (5)×10−6 °C−1. When Ti2SC was heated in air, it started to oxidize, at 400°C, first to anatase, which converts, at higher temperatures, to rutile. The sulfur and carbon atoms presumably diffuse outward and escape as gases. [Copyright &y& Elsevier]

• The effect of Mn additions on the structural and magnetic properties of AlCoCrFeNi was studied. • The arc-melted alloys consisted of a mixture of B2 and bcc phases, the relative amount of which was dependent on Mn content. • Gas atomised powders were single phase with the B2 structure. • Mn additions increased saturation magnetisation but lowered the magnetic transition temperature and the thermal stability. ga1 Alloys of AlCoCrFeMn x Ni (x = 0.0, 0.04, 0.08, 0.12 and 0.16) have been synthesized through arc–melting and gas atomisation (x = 0.0 and 0.16) to investigate the effect of Mn additions to AlCoCrFeNi. Here, the structure, magnetic properties and the thermal stability of the alloys is presented. Electron microscopy confirmed the elemental composition and revealed the microstructure to consist of two spinodally decomposed phases. Rietveld analysis of standard powder X-ray diffraction showed the arc-melted samples consisted of two phases, a B2 phase and a bcc phase while the gas atomised powders consisted of a single-phased B2 structure. Magnetic measurements revealed an increase in the saturation magnetisation at room temperature by 68% for AlCoCrFeMnNi compared to AlCoCrFeNi. The thermal stability of the alloys was investigated using magnetometry, differential scanning calorimetry and in–situ X-ray diffraction, which showed that an increase in Mn content adversely effected the thermal stability of the alloy. [ABSTRACT FROM AUTHOR]