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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]. 

The present work mainly investigated the effect of extrusion temperatures on the microstructure and mechanical properties of Mg-1.3Zn-0.5Ca (wt.%) alloys. The alloys were subjected to extrusion at 300 °C, 350 °C, and 400 °C with an extrusion ratio of 9.37. The results demonstrated that both the average size and volume fraction of dynamic recrystallized (DRXed) grains increased with increasing extrusion temperature (DRXed fractions of 0.43, 0.61, and 0.97 for 300 °C, 350 °C, and 400 °C, respectively). Moreover, the as-extruded alloys exhibited a typical basal fiber texture. The alloy extruded at 300 °C had a microstructure composed of fine DRXed grains of ~1.54 µm and strongly textured elongated unDRXed grains. It also had an ultimate tensile strength (UTS) of 355 MPa, tensile yield strength (TYS) of 284 MPa, and an elongation (EL) of 5.7%. In contrast, after extrusion at 400 °C, the microstructure was almost completely DRXed with a greatly weakened texture, resulting in an improved EL of 15.1% and UTS of 274 MPa, TYS of 220 MPa. At the intermediate temperature of 350 °C, the alloy had a UTS of 298 MPa, TYS of 234 MPa, and EL of 12.8%.