In this master's degree thesis the preparation and analyses of binary and ternary alloys between pure elements of aluminium, chromium and light rare earth, scandium is presented. Literature review of binary systems Al-Cr, Al-Sc and Cr-Sc is given, as well as classification of basic concepts of phase diagrams, their importance and description of the phase reactions and transformations that occurs in the mentioned systems. Alloys were made by vacuum arc melting in an inert atmosphere of argon, fallowed by homogenization annealing at 950 ° C and 990 ° C for 240 hours and 500 hours. Various methods were used for characterization of microstructural components in alloys and for microchemical analysis. Optical microscopy for the first insight into the microstructure, a scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) for analysing the chemical composition of detected phases in microstructure. The most important method that was used is X-ray powder diffraction (XRD), with which we identified all the phases in alloys and determined their crystal structure. Crystal structures were adapted with the Rietveld method to our experimental diffractogram. Differential scanning calorimetry (DSC) were used for all aloys where new ternary phase was detected and with DCS we investigated phase transitions in alloys. The new ternary phase, which appeared in all made ternary alloys and which has not yet been studied, has a hexagonal crystal structure with space group P63/mmc and with composition of Al from 48,0 to 58,0 at. %, Cr from 8,0 to 18,0 at. % and Sc from 33,0 to 34,0 at. % and it is predicted to be Laves phase.
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