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Osnovni namen diplomske naloge je bila izdelava in karakterizacija hitro strjenih trakov zlitine Al-Ti-V-Fe. Hitro strjene trakove smo izdelali po postopku hitrega strjevanja na vrtečem se valju. S to tehnologijo lahko dosežemo velike ohlajevalne hitrosti (med 105 in 106 K/s) in s tem velike hitrosti strjevanja. Karakteristične temperature mikrostrukturnih sprememb hitro strjenih trakov smo določili z meritvami električne upornosti in DSC analizo. Pomagali smo si tudi s programom Thermo Calc, s pomočjo katerega smo izdelali ravnotežni fazni diagram za našo zlitino. Za karakterizacijo mikrostrukture smo uporabili vrstično elektronsko mikroskopijo (SEM) in EDXS analizo. Za boljšo interpretacijo rezultatov smo izmerili tudi Vickersovo mikro trdoto na vzorcih pred in po toplotni obdelavi. Cilj raziskav je bil razložiti mikrostrukturne spremembe med vzorcem v litem stanju in toplotno obdelanim vzorcem. The basic purpose of the diploma work was to produce and characterize rapidly solidified Al-Ti-V-Fe alloy ribbons. The rapidly solidified ribbons were produced using the melt spinning method. This technology can achieve high cooling speeds (between 105 and 106 K/s) and, thus, high solidification speeds. The characteristic temperatures of the microstructural changes of the rapidly solidified ribbons were determined by electrical resistance measurements and DSC analysis. We also used Thermo Calc program to help us create an equilibrium phase diagram for our alloy. Scanning electron microscopy (SEM) and EDXS analysis were used to characterize the microstructure. We also measured the Vickers microhardness on the samples before and after heat treatment to interpret the results better. The research aimed to explain the microstructural changes between the as-cast and heat-treated samples. |
