Structural investigations of mechanical properties of Al based rapidly solidified alloys

In this study, Al based Al–3 wt.%Fe, Al–3 wt.%Cu and Al–3 wt.%Ni alloys were prepared by conventional casting. They were further processed using the melt-spinning technique and characterized by the X-ray diffraction (XRD), scanning electron microscopy (SEM) together with energy dispersive spectroscopy (EDS), transmission electron microscope (TEM), differential scanning calorimetry (DSC) and the Vickers microhardness tester. The rapidly solidified (RS) binary alloys were composed of supersaturated α–Al solid solution and finely dispersed intermetallic phases. Experimental results showed that the mechanical properties of RS alloys were enhanced, which can be attributed to significant changes in the microstructure. RS samples were measured using a microhardness test device. The dependence of microhardness HV on the solidification rate (V) was analysed. These results showed that with the increasing values of V, the values of HV increased. The enthalpies of fusion for the same alloys were determined by DSC.

► Rapid solidification processing (RSP) involves exceptionally high cooling rates.
► We correlate the microstructure of the intermetallic Al3Fe, Al2Cu and Al3Ni phases with the cooling rate.
► The solidification rate is high enough to retain most of alloying elements in the Al matrix.
► The rapid solidification has effect on the phase constitution.