Nucleation Sites For Recrystallization Research Articles

Twinning-assisted static recrystallization and texture evolution in a Mg-Gd-Y-Zr alloy

The formability and mechanical properties of magnesium (Mg) alloys are strongly related to the crystallographic basal texture. Twins play critical roles in adjusting crystallographic orientation of grains during both deformation and annealing treatment via deformation twinning and twinning-assisted recrystallization. In this study, cold rolling and subsequent annealing were conducted on a Mg-5.9Gd-3.3Y-0.5Zr alloy to investigate the recrystallization behavior and texture evolution. Electron backscatter diffraction and transmission electron microscopy techniques were applied to characterize the nucleation of recrystallized grains, especially the twinning-assisted recrystallization, at multi-scales. The results indicated that a large number of {101‾2}, {101‾1} twins and {101‾1}‐{101‾2} double twins were introduced after cold rolling. The {101‾1}‐{101‾2} double twins, double twin - grain boundary intersections and dense twin-twin intersections acted as the preferential nucleation sites for recrystallization during annealing treatment, while the coarse and parallel {101‾2} twins were unfavorable for the nucleation of recrystallized grains. Although {101‾2} tension twins are the most common twins in Mg alloys, the interface of this type of twin has strong mobility and is easy to expand. Therefore, it is generally difficult for a single {101‾2} twin to recrystallize. However, the {101‾1} compression twins and {101‾1}‐{101‾2} double twins are generally difficult to expand and can store high deformation energy, so they are conducive to becoming nucleation sites for recrystallization. During the recrystallization process, the texture type (basal texture) of the cold rolled sample remained unchanged, but the overall texture intensity was significantly reduced due to the dispersion of grain orientations brought by new grains generated by twinning recrystallization.

Investigation of the Hot Deformation Behavior and Mechanism of a Medium-Entropy CoCr0.4NiSi0.3 Alloy

The CoCrNi-based medium-entropy alloys (MEA) have been extensively investigated due to their exceptional mechanical properties at both room and cryogenic temperatures. To investigate the hot deformation behavior and the recrystallization mechanism of the CoCr0.4NiSi0.3 medium-entropy alloy, a series of deformation tests was conducted using the MMS-100 thermal simulation tester, with deformation conditions of 0.001–1 s−1/850–1150 °C. During the hot deformation process, the flow stress initially increases up to its peak value before gradually decreasing towards a steady state level. Higher flow stress levels are observed with increasing strain rate and decreasing deformation temperature. The estimated activation energy for hot deformation of this alloy is approximately 423.6602 kJ/mol. The Arrhenius-type constitutive equation is utilized to establish a modified model while incorporating power dissipation theory and the instability criterion of a dynamic material model to construct power dissipation maps and instability maps. By superimposing these maps, hot processing maps with strains of 0.4, 0.5, and 0.7 are derived. In this investigation, it is observed that regions of instability exclusively occur when the true strain exceeds 0.4. These regions of instability on the hot processing map align well with experimental findings. The suitable range of parameters for hot-working decreases as the true strain increases. The microstructure was analyzed using electron backscatter diffraction and transmission electron microscopy (TEM) techniques. The volume fraction of dynamic recrystallization (DRX) decreases with increasing strain rate but diminishes with rising temperature. The TEM characterization elucidated the mechanism of DRX in this MEA. The presence of the long-period stacking ordered (LPSO) phase was observed in both the face-centered cubic matrix and hexagonal close-packed recrystallized grains under different deformation conditions. The LPSO phase originates from the matrix at a low strain rate, whereas it is generated during recrystallization at a high strain rate. The observed increase in flow stress of the as-cast MEA is primarily attributed to the synergistic effects arising from the interaction of the dislocation with twins and the second phase. The onset of instability is effectively suppressed within a limited range through the formation of coherent second phases such as L12, LPSO, and superlattice structures resulting from phase transitions. These second phases serve as nucleation sites for recrystallization and contribute to the strengthening of dispersion. Furthermore, their interaction with dislocations and twins significantly influences both flow stress behavior and recrystallization kinetics under hot deformation. These findings not only deepen our understanding of the underlying deformation mechanisms governing MEA but also offer valuable insights for designing CoCrNi-based alloys with improved mechanical properties at elevated temperatures.

Microstructure, texture and recrystallization of heavily rolled CoCrFeNi medium entropy alloy

The microstructure and texture have been characterized in a CoCrFeNi medium entropy alloy after cold rolling to 85% and subsequent annealing at 550°C for 130 min. It is observed that the as-rolled microstructure is heterogeneous and comprises extended regions of either 〈110〉//ND or 〈111〉//ND orientations and volumes of mixed orientations. The microstructure also contains a large number of shear bands acting as preferential nucleation sites for recrystallization during annealing. Recrystallization generates annealing twins, which results in new components along the 〈110〉//ND fiber and other new orientations, thus making the texture of recrystallized regions fairly weak. Orientations demonstrating increased intensities in the recrystallization texture are identified as {113}〈332〉 and {236}〈385〉 components.

Effect of strain rate and high temperature on quasi-static and dynamic compressive behavior of forged GH5188 superalloy

GH5188 Co-based superalloy is commonly employed in aero-engine eddy current and high-temperature components. Nonetheless, current research on its response behavior and mechanisms under dynamic and temperature loading remains scarce. Therefore, this study aims to investigate the dynamic compression and related deformation mechanism of GH5188 superalloy under the coupling effect of high temperature and strain rate. Quasi-static and dynamic compression tests were conducted on the forged GH5188 superalloy at both room temperature and 1000 °C. The results indicate that the material displays impressive yield strength and plasticity, while also showing a pronounced temperature sensitivity and strain rate hardening effect. Additionally, the dynamic stress-strain constitutive relationship of GH5188 is described by the modified J-C model. Regarding the dynamic deformation mechanism, GH5188 exhibited microbands, stacking faults, and nanotwins during high-strain rate compression. At 1000 °C, GH5188 underwent discontinuous dynamic recrystallization (DDRX) and continuous dynamic recrystallization (CDRX) at strain rates of 6000 s−1 and 10000 s−1, respectively. The synergistic effect of microbands and twinning enhanced the dynamic deformation ability and strengthening effect of the material. The transformation of microshear bands generated nanotwins. The twin boundaries are high-energy zones that can provide suitable recrystallization nucleation sites, induce dynamic recrystallization process, and thus obtain a fine and uniform equiaxed grain structure.

High strength-ductility synergy and low anisotropy of Mg-4.5Al-2.6Zn-0.3Mn alloy sheet achieved by annealing after rolling

• The integration of extrusion, rolling and annealing was designed and applied. • Shear bands and twins dominate after rolling with cold rolls. • Shear bands provide nucleation sites for recrystallization during annealing. • The final sheet exhibits high strength-ductility synergy and low anisotropy. • The Mg-4.5Al-2.6Zn-0.3Mn sheet owns potential to replace commercial AZ31 sheets. Mg-4.5Al-2.6Zn-0.3Mn sheets with high strength-ductility synergy and low anisotropy were fabricated by the integration of extrusion, rolling, and annealing, which act as excellent replacements for commercial AZ31 alloys. Finer grains, lower dislocation density, and weaker basal texture endow the as-annealed sheets, instead of the as-rolled ones, with the higher performance.

Evolution of Stacking Fault and Dislocation during Dynamic Recrystallization of Inconel 625 Alloy

The purpose herein is to improve the understanding of microstructure evolution of inconel 625 alloy during the dynamic recrystallization (DRX) process. Herein, the evolution process of DRX is determined by the grain orientation spread (GOS) method, and 1100 °C is determined as the complete recrystallization temperature. Electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) techniques are used to investigate the density and morphology of dislocations and stacking faults (SFs), as well as the effects of dislocations and SFs during recrystallization. With increasing recrystallization fraction, the density of dislocations and SFs decreases gradually, the dislocation start is extended, and SFs appear on other crystal planes. The existence of dislocation and SF increases the nucleation energy and nucleation sites of recrystallization, respectively, which is beneficial to the nucleation of DRX.

Microstructure and texture evolution of ECAP-processed Mg-Ce alloy during isothermal annealing

Static recrystallization and grain growth behaviors were investigated in Mg-0.3Ce (wt%) alloy processed by equal-channel angular pressing (ECAP) for N = 1 (εeq = 0.9), 2 (εeq = 1.9), and 4 (εeq = 3.9) passes at 300 °C using route Bc and annealed at 450 °C for 5, 30, 60, and 180 min. The results demonstrated that the annealed microstructure and texture are strongly related to the strain level, second particles distribution, and fraction of dynamic recrystallization (DRX) during ECAP. At low strain (1 ECAP pass), the microstructure was very heterogeneous and the texture development changed with increasing annealing time due to the absence of sufficient recrystallization nucleation sites and pinning effect of second particles. At medium strain (2 ECAP passes), the microstructure was homogeneous, however, the texture was unstable mainly due to the limited DRX during ECAP processing leading to the preferred grain growth. At high strain (4 ECAP passes), the microstructure was homogeneous and the texture was retained throughout the entire annealing duration due to the significant amount of DRX.

Effects of cryogenic deformation on the microstructure and mechanical properties of high-strength aluminum alloys

7A85 aluminum alloy forgings were compressed at 10% to 30% deformation at room and cryogenic temperatures, followed by solid-solution treatment, water quenching, 3% cold deformation, and two-stage aging. The results indicated that cryogenic deformation increased coarse second-phase particle fragmentation and led to massive dislocation proliferation, which facilitated particle dissolution due to the formation of more interfaces and dislocation-promoted dissolution. These increased the driving force for aging precipitation and produced denser matrix precipitates and narrower grain boundary precipitate-free zones. Meanwhile, numerous dislocations provided more nucleation sites for recrystallization and thus refined grains during solution treatment. The grains were refined from 500 μm in the undeformed state to an average size of 35 μm under 20% cryogenic deformation. The excessive dislocation energy and stored deformation energy at 30% deformation caused recrystallized grain growth. The optimal mechanical properties were obtained at 20% cryogenic deformation with an ultimate tensile strength, yield strength, and elongation of 499 MPa, 435 MPa, and 13.1%, which were respectively 1.6%, 2.1%, and 37.9% higher than those of the undeformed sample. • Uniformly fine equiaxed grains and the best elongation were obtained at 20% cryogenic deformation. • Excessive dislocation energy and stored deformation energy at 30% deformation led to recrystallized grain growth. • Increasing the deformation and decreasing the temperature resulted in denser matrix precipitates. • Increasing the deformation and decreasing the temperature resulted in narrower grain boundary PFZs.

In-situ observations of static recrystallization and texture formation in a cold-rolled CoCrFeMnNi high entropy alloy

Static recrystallization and texture development in a CoCrFeMnNi high entropy alloy cold-rolled to various strains and annealed were studied. Microstructural and crystallographic evolution was recorded by identical area observations using quasi in-situ electron backscatter diffraction (EBSD). The deformation texture was preserved after recrystallization, but the texture was weakened at this stage. Shear bands served as the preferential nucleation sites for recrystallization. Thin foils of the deformed alloy were in-situ observed during heating in a transmission electron microscope (TEM). It was observed that subgrains formed from deformed microstructures by dislocation rearrangement and annihilation. The subgrains coarsened by boundary migration and coalescence. These enlarged subgrains were the viable nuclei for the recrystallized grains.

Quasi-in-situ electron backscattered diffraction investigation of twin-induced recrystallization during electrical pulse treatment in AZ61 alloy

In this work, static recrystallization induced by deformations twins in cryogenic rolled AZ61 alloy during electric pulse treatment is investigated by using quasi-in-situ electron backscattered diffraction. Besides of the {10 1- 2} tensile twins, {10 1- 1} compression twins, {10 1- 2}-{10 1- 1} double twins are also observed in the as-deformed AZ61 alloy. It has been found that recrystallization occurs preferentially at the early stage of electric pulse treatment, with {10 1- 2}-{10 1- 1} double twins and {10 1- 1} compression twins being effective nucleation sites for recrystallization. In contrast, lenticular {10 1- 2} tensile twins are consumed by surrounding grains that are with growth advantage. Our results suggest a feasible way to tailor the microstructure of Mg alloys through cryogenic rolling and electrical pulse accelerated recrystallization.

Effect of pre-twinning on microstructure and texture evolution in room and cryogenically deformed Mg-0.5Ca alloy

Introducing {10-12} tension twin lamellas has proved to be the most effective strategy to enhance the performance of Mg alloys. Twins can provide the preferential nucleation sites for recrystallization, hence twinning induced grain refinement can result in higher strength material based on Hall-Petch Effect. In addition, twinning can also modify the crystallographic c-axis distribution in wrought Mg alloys resulting in lower plastic anisotropy. Accordingly, in the present work, the twinning evolution in the Mg-0.5Ca (wt.%) alloy at room and cryogenic temperature was critically investigated. The samples were subjected to pre-compression (5%) at room temperature and -150 °C at the strain rate of 10-3 s-1. The microstructural and textural characterization was carried out using OM, SEM and EBSD to emphasize the twinning evolution during compression at room and low temperatures. The local lattice distortion and the localized deformation in terms of Kernel average misorientation (KAM) was also studied. The results revealed the significant grain refinement (13.7 μm 5.61 μm and 6.02 μm of uncompressed and RT, - 150 °C pre-compressed, respectively), where slightly enhanced twinning fraction in the sample compressed at RT was observed. Finally, remarkable increase in the yield strength was noticed in the pre-twinned samples, which was attributed to the twinning-induced grain refinement based on the Hall-Petch relationship.

Enhancing tensile strength and ductility of high-speed-extruded Mg–5Bi–2Al through trace Mn addition

The Mg–5Bi–2Al (BA52, wt%) has shown excellent extrudability despite its high alloying content. This work is conducted to enhance the strength and ductility of BA52 extrudate, which is fabricated at a very high speed, through the addition of a trace amount of Mn. The addition of 0.2 wt% Mn to BA52 causes substantial changes in the microstructure of a homogenized billet. These variations include grain refinement, formation of a semi-continuous coarse-particle network along grain boundaries, and formation of fine-particle-depletion regions near the grain boundaries. These microstructural variations provide abundant nucleation sites for recrystallization near the grain boundaries during high-speed extrusion (exit speed: 70 m/min). Consequently, grain refinement of the extrudate occurs from 29.7 to 20.0 μm with Mn addition. The BAM520 extrudate has similar basal fiber texture and internal strain energy with the BA52 extrudate. However, the former exhibits an improved tensile strength (~20 MPa greater) than the latter, which is primarily ascribed to the decreased grain size. This work demonstrates that minimal Mn addition considerably facilitates dynamic recrystallization during hot extrusion, thus improving the strength and elongation of high-speed-extruded BA52. • The addition of 0.2 wt% Mn greatly decreases the grain size of a BA52 billet. • Mn addition increases coarse Mg 3 Bi 2 particles and decreases fine Mg 3 Bi 2 particles. • Microstructural changes in a homogenized billet promote DRX during extrusion. • Tensile strength and elongation of BA52 extrudate are improved by Mn addition. • Material improvement is mainly attributed to grain refinement of the extrudate.

Effect of Reduction Rate on the Recrystallization Behavior in AA3003 Aluminum Alloy Fabricated by DC Casting

The recrystallization behavior of the cold-rolled AA3003 aluminum alloy with the reduction rate of 20%, 50% and 90% during annealing at the temperature ranging from 300°C to 400°C was investigated. As increasing reduction rate, the cold rolled specimens exhibit deformation bands with elongated grain microstructure consisting of straight grain boundary parallel to rolling direction. Therefore, large density of nucleation sites for recrystallization would be expected with increase of strain energy. The grain size of the cold-rolled specimens decreased with increase of reduction rate, c.f., as the rolling reduction increased to 90%, grain size along the direction normal to the sheet decreased to about 8μm in thick. When the sample annealed at 350°C for 5s, the first recrystallized grains were observed in the vicinity of the grain boundary. The relaxation and recrystallization kinetics under different annealing conditions were characterized in terms of the Johnson–Mehl–Avrami–Kolmogorov (JMAK) model. The apparent activation energies of recrystallization for the cold-rolled specimens with reduction rate of 20%, 50% and 90% were determined as 332 kJ/mol, 239 kJ/mol and 115 kJ/mol, respectively. XRD analysis by using modified Williamson–Hall plots revealed that the tendency of the change in dislocation density is varied depending on reduction rate. These results indicate that the apparent activation energy for recrystallization and the crystallites size decrease with increase of the reduction rate, which leads to a decrease in the size of the recrystallized grains.

Achieving high strength-ductility in pure copper by cold rolling and submerged friction stir processing (SFSP)

In this research, the combined effect of pre-rolling and submerged friction stir processing (SFSP) on the microstructure, hardness, and tensile behavior of commercially pure copper were evaluated. Several voids and cavities were observed in the stirred zone of 0 %–400, 60 %–400, 60 %–600, and 0 %–800 samples, and the defect-free copper could be achieved under a narrow process window. The microstructures revealed that a significant decrement in grain size occurred in the stirred zone of the SFSP-processed coppers due to the occurrence of dynamic recrystallization (DRX) and water cooling conditions. The pre-rolling led to decreasing the grain size after the SFSP owing to providing more nucleation sites for recrystallization. In the 60 %–800 sample, despite the increase in heat-input by increasing the rotational speed, due to the pre-strain, the average hardness was about 5 HV higher than the 0 %–600 sample (92.2 HV vs. 87.1 HV). In the case of the 0% sample, by conducting the SFSP, the yield and ultimate tensile strengths (YS and UTS) increased to 215 and 277 MPa, respectively, due to the lower grain size of the 0 %–600 sample as compared to the 0% sample (4.5 μm vs 17.9 μm). On the other hand, in the 60 %–800 sample, the YS and UTS reduced to 307 MPa as compared to the 60 % sample owing to the transition of the strengthening mechanism from strain hardening to grain refinement. The fractured surfaces of all samples exhibited a ductile manner. However, after the SFSP, the size and depth of dimples were reduced due to the finer grain size.

Micromechanical analysis of residual stress around coarse precipitates under cold rolling conditions

Characteristic microstructures of fine equiaxial grains with highly oriented gradients are often found around coarse precipitates in cold-rolled specimens; these microstructures are regarded as recrystallization nucleation sites under cold rolling and subsequent heat treatment. To predict the influence of applied strain and precipitate shape on strain and stress disturbances near a precipitate, the inhomogeneity problem under cold rolling conditions has been solved analytically using interior- and exterior-point Eshelby tensors. It is found that the stress and strain disturbances around the precipitate vary substantially with the aspect ratio of the precipitate, where the region of stress localization is dependent on the precipitate curvature at both ends of the precipitate parallel to the rolling direction. The residual stress predictions strongly suggest that the formation of a rotated zone is caused by the relaxation of disturbed stress under cold rolling.

An effective rolling process of magnesium alloys for suppressing edge cracks: Width-limited rolling

To suppress the edge crack of the magnesium alloy sheet during the ordinary rolling process, a new rolling process named width-limited rolling was proposed in this paper. Width-limited rolling is a rolling method in which the width of the alloy sheet is limited by modifying the shape of the rollers, allowing a compressive stress field to form at the edge portion of the alloy sheet during rolling, resulting in the reduction of edge cracks. At present work, magnesium alloy sheets were separately subjected to ordinary rolling and width-limited rolling. The microstructure evolution and mechanical properties of the rolled sheets were investigated by EBSD, TEM, and XRD. The results exhibited that under the same rolling conditions, the sheet after ordinary rolling exhibited obvious edge cracks while no crack was found at the edge of the sheet after width-limited rolling. The edge crack suppressing effect was attributed to the reduction of the tensile stress along rolling direction during WLR, promoting the synchronous extension of the edge and center regions to suppress edge crack tendency. Microstructure observation showed that the compressive twins formed in the sheet after ordinary rolling usually exhibited as thin plates and cannot continue to fully develop due to the premature generation of the edge cracks. However, the compressive twins developed maturely in some of which double twins formed and various slip systems with different dislocation Burgers vectors occurred in the rolled sheet after WLR. More twin intersections and shear bands, providing more potential recrystallization nucleation sites, which are beneficial to weaken basal texture. With the cooperation of twinning and dislocation slip, the texture of the sheet after the width-limited rolling is weakened and the mechanical properties are improved.

A simultaneous improvement of both hardness and ductility of Ti-6Al-4V alloy by Nb addition

Some mechanical properties of treated Ti-6Al-4V alloy such as micro hardness and ductility were investigated. Ti-6Al-4V-xNb (x = 1, 2 and 5 wt.%) alloys were produced. The influence of Nb contents on microstructure characteristics and mechanical properties showed that the addition of Nb in Ti-6Al-4V alloy persuaded the formation of new phase distributing at grain boundaries. When the Nb content increases from 0 wt% to 5 wt%, the existence of fine precipitates postponed dynamic recrystallization and refined dynamically recrystallized. The average grain size of treated titanium alloy decreased significantly from ∼20 to ∼5 µm as a function of Nb contents increasing from 0 to 5 wt%, which can be attributed to the greater number of recrystallization nucleation sites due to grain refinement of the billet. The addition of Nb simultaneously improved the microstructural homogeneity, hardness, and ductility of the extruded alloys. The significant increase of microhardness was mainly ascribed to refined microstructure and dynamic precipitates.

Effect of β Phase Decomposition on Recrystallization in α-Zr Region in Zr-2.5%Nb Pressure Tube Material

The effects of β phase decomposition on recrystallization and texture variation in Zr-2.5% Nb alloy pressure tube material were investigated. Isothermal annealing was conducted at 350 to 550 <sup>o</sup>C for 240 hours, and isothermal annealing was performed at 500 <sup>o</sup>C for 240 to 3,000 hours. The recrystallization and texture variation were analyzed by inverse pole figure variation using the XRD and EBSD methods. Annealing in α-Zr region at below 610 <sup>o</sup>C induced recrystallization and texture variation in the α-Zr. These results differ from those from a previous annealing study of the α+β region at 750-830 <sup>o</sup>C. Annealing above 400 <sup>o</sup>C for 240 hours caused β-Zr decomposition into β-Nb. The decomposition of the β-phase by annealing above 475 <sup>o</sup>C caused a contraction of 7.5% in the d(110) spacing in the β-phase, and a reduction in the volume fraction of the β phase by about 80%. It seems that the stress internally formed by the lattice contraction of the β-phase provides the driving force for recrystallization. In addition, it suggests that the newly formed α-Zr produced by β phase decomposition provides new nucleation sites for recrystallization and causes texture variation in the α-Zr. The reason why the recrystallization and the texture variation occurs only in the α-Zr stable region at below 610 <sup>o</sup>C is discussed.

Influence of cryogenic deformation on second-phase particles, grain structure, and mechanical properties of Al–Cu–Mn alloy

To refine the coarse second-phase particles (Al2Cu) and grains of Al–Cu–Mn alloy, 10% and 20% compression deformation at cryogenic and room temperatures was applied, followed by a T8 heat treatment process consisting of solution treatment, 3% cold deformation, and artificial aging. The microstructures of the compressed and heat-treated samples were investigated using a combination of scanning electron microscopy, X-ray diffractometry, electron backscattering diffractometry, and transmission electron microscopy, with the results showing that coarse Al2Cu particles are fragmented during cryogenic compression. Further, the higher dislocation densities in the cryogenically deformed samples, which lower the activation energies for atomic diffusion, promote the dissolution of particles during subsequent heat treatment. After heat treatment, the volume fraction of coarse particles decreased from 2.5% for a sample processed without deformation, to 0.5% for the sample cryogenically compressed at a ratio of 20%. Meanwhile, the higher dislocation density provides more nucleation sites for recrystallization during heat treatment. Consequently, at 33 μm, the average size of the grains in the 20% cryogenically compressed sample was much smaller than the size of the grains in the uncompressed sample (500 μm). This microstructural refinement increased the ultimate tensile strength, yield strength, and elongation from 445 MPa, 363 MPa, and 7.1% in the undeformed sample, to 471 MPa, 377 MPa, and 13.4%, respectively, in the cryogenically compressed sample.

Significant improvement in the mechanical properties of an extruded Mg–5Bi alloy through the addition of Al

This study demonstrates that the addition of Al to an Mg–5Bi alloy effectively promotes dynamic recrystallization during hot extrusion and significantly improves the mechanical properties of the extruded alloy. When the Al content increases from 0 wt% to 9 wt%, the area fraction of recrystallized grains increases from 69.3% to 100%, which can be attributed to the greater number of recrystallization nucleation sites due to grain refinement of the billet, enhanced particle-stimulated nucleation due to the greater abundance of undissolved particles, and the facilitation of dislocation accumulation due to the lower stacking fault energy. The addition of Al also simultaneously improves the microstructural homogeneity, tensile and compressive strength, ductility, and yield symmetry of the extruded alloys. The tensile yield strength × elongation value of the extruded material dramatically increases from 412 to 3489 MPa∙% with the addition of 6 wt% Al to the Mg–5Bi alloy. The variation in dynamic recrystallization and dynamic precipitation behaviors with changes in Al content and the association between the microstructural characteristics and mechanical properties of the extruded alloys are discussed in detail.