Abstract
Phase transformations in samples of industrial aluminum alloy of standard chemical composition D16 subjected to heat treatment and asymmetric rolling based on purposefully created asymmetry due to mismatch of the circumferential speeds of the rolls (V1=10 rpm and V2=1.5 rpm) were investigated using differential scanning calorimetry (DSC). Endothermic and exothermic peaks responsible for the dissolution and release of metastable and stable hardening phases are recorded on the DSC heating curve. The values of the temperatures of the beginning, peak and end of the phase transition are established. It is shown that the process of decomposition of aluminum solid solution in the alloy after asymmetric rolling has its significant differences from the decay of alloy D16 after heat treatment. For the D16 alloy sample after asymmetric rolling on the DSC curve, the presence of an endothermic peak in the temperature range 562-0, presumaly corresponding to the dissolution of the high-alloyed copper y2-phase (Cu9Al4), and its absence on the DSC curve of the sample after heat treatment, was recorded. The obtained research results are informative and significant for explaining the mechanism of hardening of aluminum alloys under intense plastic deformation, in particular, during asymmetric rolling.
Keywords:
intensive plastic deformation, asymmetric rolling, aluminum alloy, D16, DSC curve, phase transformations.