The laser engineered net shaping (LENS®) process is shown here as an alternative to melting, casting, and powder metallurgy for manufacturing iron aluminides. This technique was found to allow for the production of FeAl and Fe3Al phases from mixtures of elemental iron and aluminum powders. The in situ synthesis reduces the manufacturing cost and enhances the manufacturing efficiency due to the control of the chemical and phase composition of the deposited layers. The research was carried out on samples with different chemical compositions that were deposited on the intermetallic substrates that were produced by powder metallurgy. The obtained samples with the desired phase composition illustrated that LENS® technology can be successfully applied to alloys synthesis.

Thermodynamic properties of all reported up to date intermetallic phases in Mg-Pd equilibrium system are reported in this work. Ab initio method was applied to calculate formation energies, relaxed lattice constants and bulk moduli. The consistent set of data was obtained, including formation energies and bulk moduli of Mg 6 Pd and Mg 9 Pd 11 that were calculated for the first time. The obtained energies of formation can be used for future thermodynamic optimization of promising hydrogen storage material Mg-Pd.

La1-xCexNi5 alloys (x = 0, 0.09, 0.25 and 0.5) were investigated in terms of their structures, phase contents, hydrogen storage properties and microhardness. It was confirmed that a cerium addition to the reference (LaNi5) alloy caused structural changes such as lattice shrinkage and, as a result, changed both the absorption and desorption pressures and the enthalpies of formation and decomposition. The alloy with the highest cerium content was found to possess a two-phase structure, probably as a result of nonequilibrium cooling conditions during its manufacturing process. The microhardness was found to increase to some extent with the cerium content and decrease for samples with the highest cerium content.

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