Non-conventional hot rolling for improvement of mechanical properties in binary Mg-alloys

Abstract

Non-conventional differential speed and confined hot rolling methods were employed to process two binary magnesium-aluminum-alloys, Mg-xAl (x = 6 and 9 wt%), with conventional rolling being used as a comparative control. The study focused on the effect of the processing methods and parameters on the efficacy of grain refinement and texture evolution through dynamic recrystallization, and eventually on the mechanical properties of the as-processed materials. Key results are summarized as follows: (1) The grain size of the Mg–6%Al and Mg–9%Al alloy plates was greatly refined after rolling; the microstructure of the plates processed by differential speed rolling (DSR) showed greater refinement than those processed by conventional rolling (CR) or confined rolling. (2) For both alloy compositions, the as-rolled plates exhibited a strong {0001} basal texture, regardless of CR, DSR, or confined rolling conditions. Moreover, the basal texture intensity of the plates via DSR was lower than that of the plates processed by other rolling methods. (3) The mechanical properties were significantly improved after rolling for both alloy compositions. In particular, the anisotropy of the plates processed by DSR was reduced compared to that of the plates processed by CR.As such, our research showed that DSR holds great potential in the fabrication of bulk metal components with enhanced mechanical properties and formability.