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In this work, the structure and mechanical properties of innovative Al-Cu-Fe based alloys were studied. We focused on preparation and characterization of rapidly solidified and hot extruded Al-Cu-Fe, Al-Cu-Fe-Ni and Al-Cu-Fe-Cr alloys. The content of transition metals affects mechanical properties and structure. For this reason, microstructure, phase composition, hardness and thermal stability have been investigated in this study. The results showed exceptional thermal stability of these alloys and very good values of mechanical properties. Alloying by chromium ensured the highest thermal stability, while nickel addition refined the structure of the consolidated alloy. High thermal stability of all tested alloys was described in context with the transformation of the quasicrystalline phases to other types of intermetallics.

Pressureless reactive sintering production of iron aluminides is always connected with high porosity of the product. Previous research showed that silicon reduces the porosity significantly. In this work, the effect of alloying elements (Cu, Ni) on the reactive sintering behaviour and on the porosity of Fe-Al and Fe-Al-Si alloys was studied. Microstructure, phase composition, mechanical and tribological properties were studied as functions of alloy composition.

Reactive sintering powder metallurgy is a simple alternative to conventional melting and powder metallurgy processes. During this process, pressed powder mixture of pure metals or other precursors is transformed into bulk intermediary phases by thermally activated in situ reaction. This process was previously tested on FeAl and FeAlSi alloys. Positive eect of silicon on the reactive sintering behaviour was determined, leading to the development of novel carbon-free high-silicon FeAl20Si20 alloy (given in wt%). In this work, the eect of nickel on the pressureless reactive sintering of FeAlSi pressed powder mixtures was studied. To explain the nickel inuence, dierential thermal analysis was utilized. Microstructure, phase composition and porosity of the FeAl20Si20Nix (x = 0, 5, 10, 20 wt%) alloys was described. Hardness, wear resistance, high-temperature oxidation resistance and thermal stability were evaluated as functions of nickel content. Results showed that porosity decreases with growing nickel content down to less than 3 vol.%. Oxidation rate of these alloys is more than 10 times lower than that of original FeAl20Si20 alloy. Thermal stability and abrasive wear resistance of these alloys is also superior to FeAl and FeAlSi materials.