Composed phases and microhardness of aluminium-rich aluminium-iron alloys obtained by rapid quenching, mechanical alloying and high pressure torsion deformation

Aluminium-based Al-Fe alloys with Fe content of 2, 4, 5, 8 and 11 mass% were examined using X-ray diffraction and Mossbauer spectroscopy. The alloys were prepared by various techniques: remelting, accelerated cooling by centrifugal casting, rapid quenching from the melt at a rate of 10(6) K/s, and mechanical alloying of pure elements in high-energy planetary ball mill. It is shown that the crystalline structure refinement and the composed phases of the alloys essentially depend on the techniques used for the sample preparation. Phase transformations by severe plastic torsion deformation of the alloys prepared by various techniques were studied. The highest supersaturation of Fe in the aluminium-based solid solution can be reached using two subsequent techniques of alloy treatment: rapid quenching and high-pressure torsion.