Fabrication of MgAlZnMn alloy sheets with homogeneous fine-grained structures using high strain-rate rolling in a wide temperature range

Effect of the final rolling speeds on the stretch formability of AZ31 alloy sheet rolled at a high temperature

“…It should be noted that twinning was still the main deformation behaviour as increasing the rolling speed. This phenomenon was different from the results of AZ31 Mg alloy sheets rolled by large strain hot rolling [18], high speed rolling [16], high strain-rate rolling [15]. Guo et al [18]suggested that the DRX behaviour of the AZ31 Mg alloy rolled by large strain hot rolling (about 55%thickness reduction in one single pass) was obviously extended with increasing rolling speed.…”

“…Sanjari et al [16] found that the high-speed rolling AZ31 alloy sheet with a reduction thickness of 60% at one single pass exhibited a completed DRX structure. Zhu et al [15] reported that the homogeneous and fine grain structures of AZ31 ally sheet were obtained after high strain-rate rolling with a reduction of 80% by a single pass. These results indicated that increasing the rolling speed or strain-rate is efficient to refine the grains of the Mg alloy sheets.…”

“…It should be noted that the thickness reduction at finished rolling pass in the present work was about 20%, much lower than that in Refs. [15,16,18]. Thus, it can be inferred that the difference in the microstructures of AZ31 alloy after rolling may be due to the variety of the thickness reduction at a single rolling pass.…”

“…The better combination between tensile strength and elongation of AM50 alloy sheet could be obtained by rolling at 200 C with the roll speed of 5 m/min. Zhu et al [15] found that the HSRR AZ31 alloy sheets possessed much finer grains structures and weaker texture than that of conventionally rolled sheets, so the mechanical property of the former one was more superior.…”

Twinning, recrystallization and texture development during multi-directional impact forging in an AZ61 Mg alloy

“…Currently much effort is being put into the high-speed processing methods, such as high-speed extrusion [1,2], high strain-rate rolling [3,4] and high strain-rate forging [5][6][7][8], etc., in attempts to lower the processing cost while still retaining good mechanical properties of wrought Mg alloys. In our previous study [5], multi-directional impact forging (MDIF) with high strain rate was successfully used to fabricate the bulk AZ61 Mg materials with fine grains and non-basal texture, and consequently, enhanced strength and ductility, demonstrating that it was a highly efficient approach to enhance mechanical properties and lower cost.…”