Recrystallization stands as an essential process that influences the microstructure and properties of magnesium (Mg) alloys, yet its mechanisms remain complex and multifaceted. This review explores the key factors affecting the recrystallization behavior of Mg alloys, emphasizing how their unique structural characteristics impact the driving forces and dynamics of recrystallization. Unlike conventional alloys, Mg alloys exhibit distinctive recrystallization kinetics, which is significantly affected by deformation conditions, such as strain rate, temperature, and processing methods (e.g., rolling, forging, and extrusion). The process is also influenced by material characteristics, including initial grain size, texture, dislocation density, solute clustering, and stacking fault energy. Additionally, uneven strain distribution, stress concentrations, and stored energy play crucial roles in shaping the formation of recrystallized grains, particularly near grain boundaries. Notably, recrystallization is driven by dislocation accumulation and the availability of slip systems, with new strain-free grains typically forming in regions of high dislocation density. This paper synthesizes the existing literature to provide a comprehensive understanding of the mechanisms and kinetics of recrystallization in Mg alloys, highlighting the influence of microstructural features such as second-phase particles and grain boundary characteristics. It also identifies key challenges and suggests promising directions for future research, including optimizing material compositions and the interaction between deformation conditions via machine learning.

The effective connection of 1050 Al and AZ31 Mg was realized by magnetic pulse welding. The maximum tensile-shear force of the dissimilar Al/Mg metal lap joint reached 97% of that of the 1050 Al alloy base material by optimizing the process parameters. The microstructure of dissimilar Al/Mg welded joints was analysed by Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS) and Electron Backscattered Diffraction (EBSD). The results show that the key to obtaining high shear strength of Al/Mg dissimilar metal joints is mainly due to the following two reasons. On the one hand, grain refinement and element interdiffusion occur at the interface. On the other hand, no intermetallic compounds are formed at the interface.

Despite the industrial significance of grain size for enhancing mechanical properties and formability, the in-depth deformation mechanisms at elevated temperature are still unclear. To investigate the functions of grain size on hot workability and deformation mechanisms, three groups of Mg-1.2Zn-0.2Y alloy specimens with different grain sizes were hot compressed and then studied by combining constitutive model, processing map and microstructural observations. The results showed that the enhanced hot workability accompanying low deformation activation energy and small instability regime was obtained with refined grain size. During hot deformation, the decreased grain size in Mg-1.2Zn-0.2Y alloy mainly improved the plastic deformation homogeneity, especially for the weakened local straining around grain boundaries. As a result, the dynamic recrystallization nucleation and texture development at lower strain level were influenced by the initial grain size. At higher strain magnitude, the growth and coarsening of dynamic recrystallized grains would further release strain localization and improve hot workability, while the texture was less impacted. Further, unlike the primary basal slip and deformation twinning in the specimen with coarse grain at low temperature, non-basal slips of dislocations were initiated with less deformation twins in the specimens with refined grain size.