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Conventional rolling is a plastic deformation process that uses compression between two rolls to reduce material thickness and produce sheet/plane geometries. This deformation process modifies the material structure by generating texture, reducing the grain size, and strengthening the material. The rolling process can enhance the strength and hardness of lightweight materials while still preserving their inherent lightness. Lightweight metals like magnesium alloys tend to lack mechanical strength and hardness in load-bearing applications. The general rolling process is controlled by the thickness reduction, velocity of the rolls, and temperature. When held at a constant thickness reduction, each pass through the rolls introduces an increase in strain hardening, which could ultimately result in cracking, spallation, and other defects. This study is designed to optimize the rolling process by evaluating the effects of the strain rate, rather than the thickness reduction, as a process control parameter. 

Background: The primary hot rolling method implemented is differential speed rolling(DSR). The material is rolled and grains are strained, producing fine dynamic recrystallization(DRX) grains that improve material strength and ductility. Objective: The material introduced and under investigation in this paper is an Mg-based alloy,Mg5Zn (wt. %), whose microstructure is enhanced through a combination of heat treatments withproper temperature and holding time and subsequent plastic deformation through hot rolling toevaluate the effect on mechanical properties Methods: The method involves preheating the material to various temperatures in a range from250ºC to 350ºC and rolling to various thickness reductions to analyze the effect of single-pass differentialspeed rolling (DSR) and conventional rolling (CR) on the DRX process and its influenceon mechanical properties. Results: The effect of single-pass differential speed rolling (DSR) and conventional rolling (CR)on the DRX process shows that the process produces increasing amounts of finer DRX grains athigher rolling reductions, thereby improving the strength and ductility of the material. Conclusion: This investigation demonstrated that single-pass DSR can improve the mechanicalproperties and formability of Mg5Zn more effectively than CR in terms of grain refinement analyzedthrough OM, SEM, and EBSD resulting in enhanced tensile strength and ductility [1].