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Rechargeable magnesium batteries (RMBs), as a low-cost, high-safety and high-energy storage technology, have attracted tremendous attention in large-scale energy storage applications. However, the key anode/electrolyte interfacial issues, including surface passivation, uneven Mg plating/stripping, and pulverization after cycling still result in a large overpotential, short cycling life, poor power density, and possible safety hazards of cells, severely impeding the commercial development of RMBs. In this review, a concise overview of recently advanced strategies to address these anode/electroyte interfacial issues is systematically classified and summarized. The design of magnesiophilic substrates, construction of artificial SEI layers, and modification of electrolyte are important and effective strategies to improve the uniformity/kinetics of Mg plating/stripping and achieve the stable anode/electrolyte interface. The key opportunities and challenges in this field are advisedly put forward, and the insights into future directions for stabilizing Mg metal anodes and the anode/electrolyte interface are highlighted. This review provides important references fordeveloping the high-performance and high-safety RMBs.

A cost-effective, high-performance Mg-2.0Zn-1.5Mn alloy was fabricated using closed forging extrusion (CFE). The results reveal that CFE can promote a dynamic recrystallization (DRX) ratio and enhance the residual dislocation density in deformed grains and subgrains. Grain refinement is achieved through multiple DRX mechanisms, particle-stimulated nucleation, and pinning effects. In addition, the basal texture and precipitation behavior are significantly influenced by pre-forging in CFE. Finally, grain refinement and substantial residual dislocations result in a good combination of strength and plasticity, with the ultimate tensile strength of 400 MPa and elongation of 22.1%, respectively. A novel strategy for regulating the bimodal grain structure is proposed to guide the optimization of the mechanical performance of rare-earth free Mg alloys.

As highly integrated circuits continue to advance, accompanied by a growing demand for energy efficiency and weight reduction, materials are confronted with mounting challenges pertaining to thermal conductivity and lightweight properties. By virtue of numerous intrinsic mechanisms, as a result, the thermal conductivity and mechanical properties of the Mg alloys are often inversely related, which becomes a bottleneck limiting the application of Mg alloys. Based on several effective modification methods to improve the thermal conductivity of Mg alloys, this paper describes the law of how they affect the mechanical properties, and clearly indicates that peak aging treatment is one of the best ways to simultaneously enhance an alloy's thermal conductivity and mechanical properties. As the most frequently used Mg alloy, cast alloys exhibit substantial potential for achieving high thermal conductivity. Moreover, recent reports indicate that hot deformation can significantly improve the mechanical properties while maintaining, and potentially slightly enhancing, the alloy's thermal conductivity. This presents a meaningful way to develop Mg alloys for applications in the field of small-volume heat dissipation components that require high strength. This comprehensive review begins by outlining standard testing and prediction methods, followed by the theoretical models used to predict thermal conductivity, and then explores the primary influencing factors affecting thermal conductivity. The review summarizes the current development status of Mg alloys, focusing on the quest for alloys that offer both high thermal conductivity and high strength. It concludes by providing insights into forthcoming prospects and challenges within this field.

Mg–1Mn alloy, extruded at a low temperature in our published protocol, contributed to the intensified basal texture and extremely refined microstructure with spheroidal nanoscale precipitates dispersing throughout the matrix and along the grain boundaries, consequently resulting in the excellent mechanical properties where the alloy exhibited a tensile yield strength of 204.3 MPa and a ductility of 38.8% at room temperature. Therefore, Mg–1Mn alloy was recommended as one of the potential materials for structural applications. In the present investigation, hot deformation behavior through constitutive analysis and extrusion temperature-dependent microstructure, texture and mechanical properties of as-extruded Mg–1Mn alloy were investigated, aiming at revealing how extrusion temperature affected microstructure, texture, and mechanical properties of as-extruded Mg–1Mn alloy. X-ray diffraction patterns demonstrated that phase components of the experimental alloys consisted of the α-Mg matrix and Mn precipitates. Optical microscopy images indicated a significant increase in average grain size of the alloys as the extrusion temperature increasing from 250 °C to 400 °C. Scanning electron microscopy graphics revealed that coarsened particles identified as Mn precipitates by EDS were observed within the matrix when extrusion temperature reached 400 °C. Inverse pole figure maps of the experimental samples subjected to different extrusion temperatures in the present work exhibited the typical basal texture, suggesting that basal slip was activated hardly during the tensile stress applied along the extrusion direction. Consequently, extrusion temperature displayed the significant impact on microstructure, texture, and mechanical properties of as-extruded Mg–1Mn alloy. The alloy extruded at both 250 °C and 300 °C exhibited the strong basal texture and refined microstructure with spheroidal nanoscale precipitates dispersing within the matrix and along the grain boundaries, which contributed to their excellent comprehensive mechanical properties. The alloy extruded at 400 °C possessed the typical basal texture and coarsened microstructure, leading to the extremely poor mechanical properties. Simultaneously, the constitutive model of the Arrhenius equation based on Zener-Hollomon parameters was also established in the present investigation. Therefore, optimizing the extrusion temperature to regulate the microstructure, grain orientation distribution, and morphology of precipitates was considered as one of the effective approaches for achieving the excellent mechanical properties of Mg alloys.

As the lightest metal structural materials, Mg alloys have great application potential in transportation, aerospace, and biomedicine. However, the further application is hindered by their low strength, plasticity, and poor corrosion resistance. The preparation of Mg alloys with ultra-fine grain (UFG) structure is regarded as a good solution to improve their performance, and has been reported by a large number of literatures. The purpose of this paper is to summarize the development of fabrication processes of UFG Mg alloys and the effects of UFG structure on the mechanical properties and corrosion resistance. In essence, this review aims to elucidate the evolution and current state of UFG structure in Mg alloys. Additionally, it seeks to expound upon the strategies for designing and preparing these structures and shed light on the future development trends. The ultimate goal is to advance the utilization of UFG Mg alloys in both structural and functional materials.

Magnesium (Mg), being the lightest structural metal, holds immense potential for widespread applications in various fields. The development of high-performance and cost-effective Mg alloys is crucial to further advancing their commercial utilization. With the rapid advancement of machine learning (ML) technology in recent years, the ``data-driven'' approach for alloy design has provided new perspectives and opportunities for enhancing the performance of Mg alloys. This paper introduces a novel regression-based Bayesian optimization active learning model (RBOALM) for the development of high-performance Mg-Mn-based wrought alloys. RBOALM employs active learning to automatically explore optimal alloy compositions and process parameters within predefined ranges, facilitating the discovery of superior alloy combinations. This model further integrates pre-established regression models as surrogate functions in Bayesian optimization, significantly enhancing the precision of the design process. Leveraging RBOALM, several new high-performance alloys have been successfully designed and prepared. Notably, after mechanical property testing of the designed alloys, the Mg-2.1Zn-2.0Mn-0.5Sn-0.1Ca alloy demonstrates exceptional mechanical properties, including an ultimate tensile strength of 406 MPa, a yield strength of 287 MPa, and a 23% fracture elongation. Furthermore, the Mg-2.7Mn-0.5Al-0.1Ca alloy exhibits an ultimate tensile strength of 211 MPa, coupled with a remarkable 41% fracture elongation.

Twinning is a significant deformation mode in zirconium (Zr). Here we investigated the primary displacement cascades near the twin boundary (TB) and mechanical properties in Zr using molecular dynamics simulations. The results show that {10 1‾2} and {10 1‾1} TBs can act as an effective sink for point defects to enhance irradiation resistance in Zr. The {10 1‾2} TB exhibits better sink efficiency than {10 1‾1} TB. Hence, it's recommended to employ Zr alloys with more {10 1‾2} deformation twinning microstructure in irradiation conditions. The present work predicts the introduction of TBs may contribute to a decrease in the density of large-sized clusters and clustered fraction. Further, irradiation leads to localized deformation of the two TBs even in one single collision cascade. The tensile loading of the unirradiated and irradiated samples indicates that the stacking faults serve as an important deformation mechanism in two TB models. The results not only present a reference for understanding the TB structure in the displacement cascades of Zr and its alloys but also provide further support for the design of irradiation-resistant nanotwinned metals.

Biodegradable magnesium (Mg) alloys are expected to be promising materials for cardiovascular stents (CVS), which can avoid the long-term clinical problems of current CVS, such as in-stent restenosis, late stent thrombosis, etc. Mg alloy stents exhibit superior biocompatibility and tunable biodegradability, compared with conventional permanent metallic stents. However, the poor formability and non-uniform corrosion of Mg alloy stents hinder their clinical application of CVS. This review focuses on the development of Mg alloys for CVS in recent years. According to the results of bibliometric analysis, we analyzed different biodegradable Mg alloy systems. Moreover, the structural design strategies for Mg alloy stents that can reduce the stress concentration, as well as the surface modification methods to control the corrosion behavior and biological performance of Mg alloy stents are also highlighted. At last, this review systematically discussed the potential directions and challenges of biodegradable magnesium stents (BMgS) in cardiovascular fields.

This study investigates the impact of Gd elements on the enhancement of ductility in the Mg–Gd–Zr alloy. The deformation behavior at room temperature of the cast Mg–Gd–Zr alloy and the cast Mg–Zr alloy was examined using the EBSD-assisted slip trace method. The quantitative analysis of the initiation ratio of each slip system in the two alloys revealed that the Mg–Gd–Zr alloy had a higher ratio of non-basal slip systems. The experimental determination of the critical resolved shear stress (CRSS) ratios of non-basal slip to basal slip for both alloys indicated that the Gd elements could reduce this ratio, facilitating the initiation of more non-basal slip systems to accommodate strain. Furthermore, the segregation of Gd elements at grain boundaries was observed to enhance the grain boundary strength of the alloy, which is a significant factor in the enhancement of ductility.

In this work, plasma electrolytic oxidation (PEO) coatings were produced on magnesium alloy AZ31 in aluminate, silicate and phosphate- based electrolytes, and followed by hydrothermal treatments in order to synthesis layered double hydroxides (LDHs) based nanocontainers. LDHs synthesis was done in three different growth solutions (deionized water, sodium nitrate and aluminum nitrate containing solution). In frame of this work it was shown, that it was difficult to form LDHs on Si-based PEO coating, due to more stable silicate phases in comparison with aluminate and phosphate phases in respective PEO coatings. The obtained hybrid LDH/PEO coatings were characterized using SEM, EDS and GDOES, and then the corrosion protection was further investigated by EIS. Based on the obtained results, it was confirmed that, the hydrothermal treatments in Al3+ containing solution played an important role on overall corrosion resistance for phosphate and silicate-based PEO coatings, but not for Al-based PEO coatings.

Diffusion couples for the Mg–Ag–Zn system were prepared using hcp-Mg single-phase solid solution alloys and pure magnesium (Mg). Their diffusion behaviour at 675–753K was analysed and the related diffusion coefficients were obtained. Combining these experimental results and the thermodynamic description, the atomic mobility parameters were optimised, and the kinetic database of the Mg–Ag–Zn ternary system was constructed for the first time. According to the thermodynamic and kinetic descriptions, the diffusion coefficients for concentration range of hcp-Mg (silver (Ag): 0–3 at% and zinc (Zn): 0–3 at%) were calculated. Finally, the composition and temperature dependence of the interdiffusion coefficients was further discussed using first-principles calculations and thermodynamic factors.

Owing to the features (high safety, inexpensive and environmental friendliness) of aqueous rechargeable Mg-ion batteries (ARMIBs), they have drawn extensive attention in the future energy storage systems. However, the poor Mg2+ migration kinetics during the Mg2+ intercalation/extraction still hinders the progress of developing suitable cathode materials. Herein, a layered buserite Mg-Mn oxide (MMO) material with large interlayer space (∼9.70 Å) and low-crystalline structure is studied as a high-performance cathode in ARMIBs. Compared with the counterpart, the Mg2+ migration kinetics of the MMO cathode can be enhanced by its unique structure (bigger interlayer spacing and low-crystalline structure). The layered buserite MMO as a high-performance ARMIBs cathode exhibits high Mg storage capacity (50 mA g−1: 169.3 mAh g−1), excellent rate capability (1000 mA g−1: 98.3 mAh g−1), and fast Mg2+ migration (an average diffusion coefficient: ∼4.21 × 10−10 cm2 s−1) in 0.5 M MgCl2 aqueous electrolyte. Moreover, the MMO-1//AC full battery achieved a high discharge capacity (100 mA g−1: 111 mAh g−1), and an ignored fading over 5000 cycles (1000 mA g−1). Therefore, layered Mg-Mn oxide with large interlayer space may break a new path to develop the promising ARMIBs.

Grain size is the critical characteristic of ultra-fine grain Magnesium (Mg), which is a concrete representation of the whole heat deformation procedure. In this paper, a design strategy was proposed to quantitatively investigate the composition and process conditions for the preparation of ultrafine grains. Herein, a dataset of Mg–Mn-based wrought alloys was constructed, and the average grain size was set as the design target. Based on this dataset, five machine learning (ML) algorithms, including the k-nearest neighbor (kNN), support vector machine (SVM), decision tree (DT), random forest (RF), and artificial neural network (ANN), were integrated to conduct in-depth analysis and make predictions. Among these models, the computational accuracy of both the DT classifier and ANN predictor is around 90%. The main factors affecting the formation of ultrafine grains were found by ML, and the interrelationships between the features were quantitatively analyzed as well. Then, four suggested routes with conditions were extracted from the tree models for preparing ultrafine grain Mg alloys. And four new Mg alloys were designed through these routes and taken as experimental validation. After testing, the actual grain sizes are close to the predictions, and the accuracy of the experimental verification exceeds 80%. Compared with conventional “trial and error” design methods, the grain design strategy proposed in this paper brings new thought and good prior guidance for developing high-performance commercial Mg alloys.

This work systematically investigates the impact of the dilute Sc addition on microstructures and mechanical properties in Mg alloys. Electron back scattered diffraction, slip traces analysis, transmission electron microscopy, and visco-plastic self-consistent polycrystal constitutive (VPSC) modeling were performed to investigate the deformation mechanisms in the tensile testing, especially the activation of slip. The results showed that as-solid solution samples only consisted of α-Mg phase. After extrusion, all samples exhibited a similar average grain size. With the increment of the Sc content, the ductility of the samples was significantly improved, which failure elongation (FL) of Mg-xSc (x = 0.3, 0.6, 0.9 wt.%) alloys improved from 14.4% to 24.8%. The yield strength of each alloy is similar, about 200 MPa. VPSC results indicated that the difference value of the initial slip resistance (τ0) between prismatic slip and basal slip decreases from 63 MPa to 49 MPa, and the difference value of τ0 between pyramidal slip and basal slip decreases from 72 MPa to 57 MPa. The VPSC and the two-beam diffraction results confirmed that the pyramidal slip and prismatic slip were activated in tensile testing. The quantitative analysis of the slip trace line verified that the volume of non-basal slip reached 49.5% when the Sc content increased to 0.9 wt.%. Therefore, the addition of Sc in solid solution increased the amount of pyramidal and prismatic dislocation activities during the deformation process, which was beneficial to coordinate the c-axis strain, and finally improved ductility of Mg alloy.

The solution behavior of alloying elements is crucial for the design of Mg alloys. The plasticity, strength and corrosion resistance of Mg alloys can be tailored by alloying elements in solid solution in the primary Mg phase. In this work, the interaction and solution behavior of 24 alloying elements in Mg alloys, including 24 binary systems and 88 ternary systems, was studied. Features characterizing the interactions of solute elements in the primary Mg phase, including atomic substitutional sites, volume difference, c/a ratio and formation energy, of these alloys were calculated by first principles. Relations between the interaction features and the alloying elements’ characteristics were constructed based on machine learning methods, in which strong correlations were observed. Additionally, the electronic and atomic origin of the interaction features in solid solution ternary Mg alloys were analyzed. This work provides new insights into the design of high-performance multicomponent Mg alloys, as well as the construction of atomic models for other alloys.

The recrystallization behavior of extruded Mg–Zn–Mn alloys was systematically investigated under different aging treatment prior to extrusion. Electron backscattered diffraction analysis was used to explore the recrystallization mechanism and corresponding effects on the basal texture of alloys during extrusion. The results show that the primary coarse particles can effectively promote recrystallization nucleation. Moreover, the precipitation of nanoscale particles during the aging process play a role in pinning the grain boundaries. Therefore, after peak-aged treatment (16 h), the extruded Mg alloy obtains uniform and fine microstructure, showing good mechanical properties: the tensile yield strength, tensile strength, elongation, compressive yield strength, and tension-compression yield asymmetry were 298 MPa, 363 MPa, 26%, 260 MPa, and 0.87, respectively.

The solution behavior of a second element in the primary phase (α(Mg)) is important in the design of high-performance alloys. In this work, three sets of features have been collected: a) interaction features of solutes and Mg obtained from first-principles calculation, b) intrinsic physical properties of the pure elements and c) structural features. Based on the maximum solid solubility values, the solution behavior of elements in α(Mg) are classified into four types, e.g., miscible, soluble, sparingly-soluble and slightly-soluble. The machine learning approach, including random forest and decision tree algorithm methods, is performed and it has been found that four features, e.g., formation energy, electronegativity, non-bonded atomic radius, and work function, can together determine the classification of the solution behavior of an element in α(Mg). The mathematical correlations, as well as the physical relationships among the selected features have been analyzed. This model can also be applied to other systems following minor modifications of the defined features, if required.

Within the scope of this study, the evolution of microstructures and mechanical properties in as-extruded Mg–Sc alloys were systematically explored with Mn content from 0.3 to 0.9 wt.%. The results showed that a completely recrystallized crystal structure was obtained in Mg-xMn-Sc alloys, and the average grain size decreased from 12.75 to 3.35 μm with the increase of Mn content. In addition, the increment of Mn content reduced the texture intensity from 14.95 to 7.65. Thus, Mg–Sc alloys’ tensile yield and ultimate strength significantly improved. Meanwhile, Mn addition led to the activation of non-basal slip, especially prismatic slip, which significantly enhanced the ductility of alloys. Moreover, the activation of non-basal slip by alloying Mn can be attributed to the reduction of the critical shear stress (CRSS) gap between basal slip and non-basal slip.

This work produced a MgAl-layered double hydroxide by hydrothermal treatment of a plasma electrolytic oxidation (PEO) coating on magnesium alloy AZ31 in an phosphate electrolyte, followed by an ion-exchange reaction in 0.1 M phosphate solution. The coated specimens were scratched. Characterization, including utilization of the localized technique SIET, measured the pH and pMg distributions and optical morphologies around the artificial defects during immersion in 0.05 M NaCl solution. In contrast with phosphate loaded PEO/LDHs, a stronger alkalinization area (with pH 11.4∼12.3) appeared in the passive PEO specimens. Due to formation of insoluble Mg(OH)2 products, the pMg map showed depletion of Mg2+ in this high pH area. Combined with optical morphologies and SEM images, the better self-healing ability toward defects for phosphate loaded PEO/LDHs was confirmed.

It is necessary to strictly control the iron (Fe) impurity in Mg-Al alloys to guarantee good corrosion resistance and mechanical properties. In this work, the effects of alloying elements and temperatures on the solubilities of Fe in the Mg-Al-based alloy melts (Mg-rich liquid phases) at 963–1033 K were studied by combining the in situ sampling method for the high precision solution values and the multiple regression numerical analysis method for the feature analysis. The solubilities of Fe in Mg-xAl (x = 1 and 3 wt.%) alloy melts could be significantly reduced by adding the yttrium (Y) or manganese (Mn) elements. However, the solubilities of Fe in Mg alloy melts were not in a monotonous relationship with the contents of the alloying elements in the Mg alloys. For the addition of Mn or Y, the lowest solubilities of Fe presented in the Mg-rich liquid phases were for the Mg-xAl alloys with the addition of 2 wt.% Mn or 1 wt.% Y, respectively. Additionally, the Fe-containing precipitations in the related systems were analysed and the Fe was mainly combined with Mn or Y and precipitated, which contributed to the removal of Fe from the Mg melt. The present study provides fundamental thermodynamic information regarding Mg-Al-Fe based systems and the design principle for the removal of Fe in Mg alloys.

The additions of alloying elements can significantly improve the mechanical properties of magnesium (Mg) alloys, mainly due to the fact that their additions change the critical shear stresses (CRSS) for dislocation slips. In this work, experimental and computational methods were used to explore the mechanisms responsible for the roles of Sm element addition in affecting the mechanical properties of Mg. The results showed that the addition of Sm obviously improves the microstructure and mechanical properties. It promotes the formation of twins and beneficially activated the non-basal slip at the initial stage of plastic deformation, resulting in a high ductility. The Visco-Plastic Self-Consistent (VPSC) and the two-beam diffraction results confirmed that the pyramidal slip and prismatic slip were activated during tensile testing. The quantitative analysis of slip traces verified that the volume of non-basal slips reached 35 % after Sm addition. The additions of Sm with solid solution increased the activities of pyramidal dislocation during deformation, which was beneficial to accommodate the c-axis strain, and finally improved the room temperature ductility of Mg. First-principle calculations demonstrate that the solute Sm atoms would reduce the stacking fault energy for basal and prismatic slips.

Ternary magnesium-based alloys with an aluminum content of 0.5 wt.% and a varying manganese content of x = 1, 2, and 3 wt.% (Mg-xMn-0.5Al) were prepared and characterized. The study focused on the effect of Mn addition on the formation of ultrafine grains (UFGs, average grain size

Abstract Corrosion inhibitors 2,5-pyridinedicarboxilate (PDC), sodium metavanadate (SMV) and 5-aminosalicylate (AS) were impregnated into porous PEO coatings respectively via vacuuming process, followed by fast sealing treatment in a Ce containing solution. After that layered double hydroxides (LDHs) based nanocontainers were respectively prepared on them via hydrothermal treatment. In frame of this work it was shown, that sealing effect for the pore was provided by formation of new phase CeO2 on the surface of PEO coatings. And, hydrothermal preparation for preparing LDHs leaded obvious changes in structure and thickness of the coatings. In addition, impregnation of inhibitors was in favor of improving LDHs content in final composite coatings. EIS result indicated that AS/Ce-HT specimen exhibited a best corrosion protection.

A one-step electrodeposition method was used to construct a superhydrophobic coating on the surface of magnesium alloy. Using magnesium nitrate and ethanol solution of stearic acid as electrolyte, four groups of electrolytes with different ratios of stearic acid and magnesium nitrate were designed to explore the influence of electrolyte to the process. The contact angles of the four coating samples were 136.4 ± 5.8°, 152.7 ± 2.8°, 156.2 ± 4.9° and 155.1 ± 4.4° The addition of magnesium nitrate in the solution increased the hydrogen evolution reaction in the electrodeposition process, which was not conducive to electrodeposition process. During the deposition process, the sample prepared in a molar ratio of stearic acid to magnesium nitrate of 10:1 had the best corrosion resistance, and its corrosion circuit density was 3.74 × 10−8 A/cm2, far lower than the corrosion current density of the magnesium alloy substrate. Keywords: Magnesium alloy, Superhydrophobicity, Corrosion resistance

Zirconium alloys are subjected to a fast neutron flux in nuclear reactors, inducing the creation of a large number of point defects, both vacancy and self-interstitial. These point defects then diffuse and can be trapped by their different sinks or can cluster to form larger defects, such as vacancy and interstitial clusters. In this work, the trapping capability of small-vacancy clusters (two/three vacancies, V2/V3) in the α-Zr doped with alloying elements (Sn, Fe, Cr, and Nb) has been investigated by first-principle calculations. Calculation results show that for the supercells of α-Zr containing 142-zirconium atoms with the two-vacancy cluster, alloying elements of Sn and Nb in the second vacant site (V2) and Cr in the first vacant site (V1) are more easily trapped by two vacancies, respectively. However, the two sites are both captured more easily by two vacancies for Fe in the supercells of α-Zr containing 142-zirconium atoms inside due to the similar value of the Fermi level. For the supercells of α-Zr containing 141-zirconium atoms with the three-vacancy cluster, the alloying element of Sn in the third vacant site (V’3), Fe in the first vacant site (V’1), and Cr and Nb in the second vacant site (V’2) are more easily trapped by three vacancies, respectively.

The effect of titanium on the microstructure, the texture, and the mechanical properties of as-extruded Mg–Sn alloy has been investigated in the present work. The result reveals that the alloy subjected to the optimized extrusion process shows an extremely refined microstructure with an average grain size of 1.7 μm. Meanwhile, the addition of titanium has an obvious effect on intensifying the basal texture where the basal slip cannot be easily activated during tensile testing. As a result, the alloy shows excellent mechanical properties where yield strength and elongation are 200 MPa and 30.2%, respectively. The enhanced yield strength of the alloy can be attributed to the extremely refined microstructure and the intensified basal texture, while the improved elongation of the alloy can be explained by the ultra-fine-grained microstructure through reducing the critical resolved shear stress that favors the prismatic slip activity to accommodate the basal slip.

A novel grain refinement method using a CaMgSn intermetallic phase was investigated via adding a Mg–CaMgSn master alloy to an AZ31 magnesium alloy. The results showed a remarkable grain refinement effect in as-cast AZ31, with the average grain size reduced from approximately 260–93 μm after adding 0.45 wt.% CaMgSn particles. The added CaMgSn phase was found in grain interiors and acted as heterogeneous nucleation sites during solidification. The edge-to-edge matching model confirmed a low mismatch value of 2.3% for the {0002}Mg/{211}CaMgSn close-packed plane, suggesting that {211}CaMgSn was the possible matching plane for Mg nucleation. The microhardness and compressive yield strength were also improved by adding CaMgSn particles, confirming that adding Mg–CaMgSn master alloy was an effective method for refining the microstructure and improving the mechanical properties of Mg–Al-based alloys.

The effects of Nb concentration and temperature on the generalized stacking fault energy (GSFE) of basal, prismatic I, pyramidal I and II plane for Zr-Nb alloys are investigated by molecular dynamics simulations (MD). The stable and unstable SFEs of different slip systems show no significant change with the increasing Nb concentration (0, 0.5, 1.0, 1.5, 2.0, and 2.5 at.%) in Zr-Nb alloys at 0 K. Basal, pyramidal I and II planes slip of Zr-Nb alloys prefer to deform by full dislocation with the temperature increases. Additionally, plastic deformation anisotropy of Zr-Nb alloy is improved with the increasing temperature using both embedded atom method (EAM) and angular-dependent potentials (ADP). The present work provides a theoretical basis for understanding enhanced plasticity of Zr-Nb alloys under finite temperature.

The effect of Mn on the microstructure and mechanical properties of as-extruded Mg-0.5Sr alloy were discussed in this work. The results showed that high Mn alloying (2 wt.%) could significantly improve the mechanical properties of the alloys, namely, the tensile and compressive yield strength. The grain size of as-extruded Mg-0.5Sr alloys significantly was refined from 2.78 μm to 1.15 μm due to the pinning effect by fine α-Mn precipitates during the extrusion. Moreover, it also showed that the tensile yield strength and the compressive yield strength of Mg-0.5Sr-2Mn alloy were 32 and 40 percent age higher than those of Mg-0.5Sr alloy, respectively. Moreover, the strain hardening behaviors of the Mg-0.5Sr-2Mn alloy were discussed, which proved that a large number of small grains and texture have an important role in improving mechanical properties.

High performance Mg−6Al−3Sn−0.25Mn−xZn alloys (x = 0, 0.5, 1.0, 1.5, and 2.0 wt %) without rare earth were designed. The effects of different Zn contents on the microstructure and mechanical properties were systematically investigated. The addition of Zn obviously refines the as-cast alloys dendritic structure because of the increase in the number in the second phase. For the as-extruded alloys, an appropriate amount of Zn promotes complete recrystallization, thus increasing the grain size. As the Zn content increases, the texture gradually evolves into a typical strong basal texture, which means that the basal slip is difficult to initiate. Meanwhile, the addition of Zn promotes the precipitation of small-sized second phases, which can hinder the dislocation movement. The combination of texture strengthening and precipitation strengthening is the main reason for the improvement of alloys’ strength.

Higher pressure die casting (HPDC) AM series (Mg-Al-Mn) Mg alloys have wide application potential in the automobile industry. To promote its application, systematic investigation on the corrosion performance and corrosion residual strength of HPDC AM50+1Ce and AM60 was carried out. The corrosion of HPDC AM50+1Ce was more uniform, while the pitting corrosion of AM60 was more severe, and the mechanical properties of HPDC AM60 was more sensitive to corrosion. The residual strength of AM50+1Ce and AM60 after corrosion of 648 h was 199 MPa and 183 MPa, respectively. The findings can contribute to a better understanding of the corrosion and residual strength of HPDC AM series Mg alloys.

The effect of B addition on the microstructure and mechanical properties of AM50 was investigated, and the mechanism of grain refinement was clarified. Optical microscopy, X-ray diffraction, scanning electron microscopy, and electron probe microanalysis were used to characterize the microstructure evolution. The grain size of as-cast AM50 decreased from 550 μm to 100 μm with the B content increasing from 0 to 0.15 wt.%. AlB2 particles in the Al-3B master alloy transformed to Mg-B, and acted as the grain refiner. The addition of B to as cast AM50 alloy results in improved mechanical properties of AM50 + xB alloys. For instance, the YTS (yield tensile strength), UTS (ultimate tensile strength), and elongation of as cast AM50 + 0.15 wt.% B alloy was 94 MPa, 215 MPa, and 12.3%.

A newly developed Mg-2Gd-0.5Zr-xZn (x = 0.5, 1.0, 2.0, 3.0 wt %) alloy system exhibits significant strengthening by doping with Zn. In order to understand the strengthening mechanism, the microstructure, texture evolution, and mechanical properties of ultrahigh ductility Mg-2Gd-0.5Zr alloys with a Zn addition were systematically investigated. The addition of Zn results in the formation of Mg-Gd-Zn intermetallic compounds along grain boundaries, which encourages grain refinement during hot extrusion via the particle stimulated nucleation (PSN) mechanism. Furthermore, during texture sharpening the pole changes from to , which also occurred in the extruded alloys with Zn addition, which is unfavorable for the basal slip and tensile twinning. Mg-2Gd-0.5Zr-3Zn shows well-balanced strength and ductility with a tensile yield strength (YS) and ultimate tensile strength (UTS) of 285 and 314 MPa, accompanied by a high tensile elongation of 24%. They are superior to those of commercial AZ31. The enhanced strength is attributed to grain refinement, precipitation strengthening, and texture sharpening induced by alloying with Zn. The research result is also of great value to the development of low rare-earth, high strength, and high room temperature ductility magnesium alloy.

Hot rolling was carried out in this study to modify the microstructures of an extruded Mg–6Al–1Sn–0.3Mn alloy sheet and investigate its effects on mechanical properties. After hot rolling, the grains and second phase of the extruded alloy sheet were remarkably refined, and the c-axis of a few grains was parallel to the transverse direction. The strength improvement was mainly attributed to the grain and Mg17Al12 particle refinement due to the Hall–Petch effect and the Orowan mechanism. The random orientation of the fine grains resulted in improving ductility and anisotropy.