Microstructures and Properties of Rapidly Solidified AlCrFe Extruded Profiles.

摘要

The study describes properties of AlCrFe alloys produced by the extrusion of rapidly solidified melt-spun ribbons and atomized powders. Depending on composition, microstructures of input particles consisted of interconnected crystalline Al_7Cr skeleton, filled with supersaturated α-Al phase with embedded nano-metric quasicrystalline Al84,6Cr15,4 precipitates. The direct extrusion at 450℃ yielded sound compacts and accommodated no major structural changes. Compacts showed high room temperature tensile strengths and good ductility. Long-term thermal stability of compacts up to 300℃ was proved. Thermal stability was accompanied with superior mechanical properties of compacts determined at 300℃. Cr and Fe contents were optimised in terms of compacts microstructures and by means of tensile and creep tests. AlCr5Fe0,85 (at. %) was found to be optimum composition. Found features predetermine AlCr5Fe0,85 for service at elevated temperatures. Successful up-scaling was made. Profiles of industrially extruded atomized AlCr5Fe0,85 powders of regular particle size with the same properties as laboratory material were produced.