Abstract
New approach where hard-to-deform AlFe2V4 melt-spun ribbons (MSR) were compacted into sound profiles using “non-degrading” plasticizer is shown. The plasticizer, made of 1 µm Al 99.7 % powder, enabled significant reduction of extreme loads required for extrusion of plain AlFe2V4 MSR and meanwhile improved the plasticity of extruded compacts. After extrusion plasticizer forms a “matrix” part of two-phase composite structure, which is reinforced with chopped AlFe2V4 MSR flakes. No apparent phase transformation took place even after long term annealing held at 350°C, neither within any of compact’s constituents. Unique structural stability of extruded “composites” was attributed to randomly oriented icosahedral particles, with traces of an amorphous phase and fcc Al10V intermetallic phase in AlFe2V4 MSR and to efficient strengthening by homogeneously distributed nanoscale dispersoids coming from broken surface oxides of original 1 µm Al powder plasticizer particles. Room temperature ductility and fracture toughness of mixture compacts were significantly improved in comparison to plain AlFe2V4 MSR compacts. The prepared material reproducibly attained the strength above 500 MPa at 3-4 % ductility. Outstanding mechanical properties were attained especially at elevated temperatures (UTS ~ 280 MPa and ductility of 4-5 % at 300°C). The suggested technological approach enables real utilization of RS ribbons in bulk structural profiles, whereas most of conventional technological equipment can be used for this purpose without need of intensive new investments.

Key words
aluminium, rapid solidification, high strength, heat resistance, powder metallurgy, melt-spinning, extrusion

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