Realization of low-temperature superplasticity in Mg–Al–Zn alloy sheets processed by differential speed rolling

Effect of roll speed ratio on microstructure evolution and mechanical properties of 0.18 wt% carbon steel deformed by differential speed rolling

“…A number of studies have shown that ultrafine grains (in the sub-micrometer or even nanometer range) can be achieved by imposing extremely large plastic strains through processing using severe plastic deformation (SPD) [1][2][3]. Among SPD methods, the differential speed rolling (DSR) process was known as a promising method with the potential for the continuous production of large bulk sheet materials suitable for industrial applications [4][5][6][7][8][9][10][11][12][13][14]. In performing DSR, a sample in the form of sheet is subjected to intense plastic strain by rolling the sample utilizing two rolls with identical dimensions, but with different speeds controlled by their own motors, generating the shear strain which was imposed uniformly through the sheet.…”

Factors influencing tensile ductility of ultrafine-grained Mg–3Al–1Zn alloy sheet at elevated temperatures

“…At temperatures above 448 K, the m values of UFG AZ31 are in range between 0.22 and 0.3. According to the deformation mechanism maps for Mg alloys, grain-boundary-diffusion-controlled GBS associated with m = 0.5 and pipe-diffusion-controlled slip creep associated with m = 0.14 compete each other at warm temperatures [8]. As the m values of UFG AZ31 are obviously larger than 0.14, GBS is likely contribute to plastic flow to some extent and thus flow stress is affected by grain size.…”

MICROSTRUCTURAL EVOLUTION OF AZ31 MAGNESIUM ALLOY PROCESSED BY A NEW NOBLE SEVERE PLASTIC DEFORMATION METHOD

“…"An effective tactic to minimize these disadvantages is to develop magnesium alloys with fine grained microstructures. 7 " However a few works on this topic can be found in the literature. "AZ31 alloy was successfully ECA deformed for 8 passes with the application of a moderate back pressure and bimodal structure with grains of as fine as 0.5 µm.…”