A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The resu...A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The results show that cold-pressing produces intense plastic deformation near the corrugated surface of the Al plate,which promotes dynamic recrystallization of the Al substrate near the interface during the subsequent hot-pressing.In addition,the initial corrugation on the surface of the Al plate also changes the local stress state near the interface during hot pressing,which has a large effect on the texture components of the substrates near the corrugated interface.The construction of the corrugated interface can greatly enhance the shear strength by 2−4 times due to the increased contact area and the strong“mechanical gearing”effect.Moreover,the mechanical properties are largely depended on the orientation relationship between corrugated direction and loading direction.展开更多
Additive manufacturing(AM)methods have garnered considerable attention owing to their flexibility in fabricating complex parts with desirable mechanical properties.However,the poor surface quality of the resulting met...Additive manufacturing(AM)methods have garnered considerable attention owing to their flexibility in fabricating complex parts with desirable mechanical properties.However,the poor surface quality of the resulting metal parts remains a severe challenge for the applications.Here,a novel dual-additive synergy strategy is presented,which simultaneously enhances material removal efficiency and regulates electrode surface reactions during electrochemical polishing(ECP)of AM AlSi10Mg.Theoretical studies and experimental characterizations confirm that NaF promotes selective dissolution at the peaks,while glucose acts as a stabilizer for the surface valleys.This approach effectively facilitates the selective removal of surface protrusions,achieving a smoother and more uniform surface finish,resulting in a surface roughness reduction of approximately 86%,compared to a 63%reduction without additives.This study not only provides a new approach for optimizing surface quality of AM AlSi10Mg but also offers new insights into electrolyte design and the stabilization of metal anodes.展开更多
Magnesium alloys have gained extensive applications across various industries,including aerospace,transportation,and civil construction,owing to their excellent combinations of high specific strength and stiffness[1]....Magnesium alloys have gained extensive applications across various industries,including aerospace,transportation,and civil construction,owing to their excellent combinations of high specific strength and stiffness[1].However,their lim-ited strength due to the lack of effective strengthening phases has hindered their broader industrial applications[2].Never-theless,it has been challenging to achieve significant strength-ening due to the restricted solubility of alloying elements in magnesium[3].Thus,more and more efforts have been made to explore the concept of secondary phase-reinforced magne-sium alloys[2,4,5],where the secondary phase acts as re-inforcing agents within the magnesium matrix,resembling a composite material.展开更多
The accelerating factor （AF） method is a simple and appropriate way to investigate the atomic long-time deep diffusion at solid-solid interface. In the framework of AF hyperdynamics （HD） simulation, the relationsh...The accelerating factor （AF） method is a simple and appropriate way to investigate the atomic long-time deep diffusion at solid-solid interface. In the framework of AF hyperdynamics （HD） simulation, the relationship between the diffusion coefficient along the direction of z-axis which is normal to the Mg/Zn interface and temperature was investigated, and the AF＇s impact on the diffusion constant （D0） and activation energy （Q^＊） was studied. Then, two steps were taken to simulate the atomic diffusion process and the formation of new phases： one for acceleration and the other for equilibration. The results show that： the Arrhenius equation works well for the description of Dz with different accelerating factors; the AF has no effect on the diffusion constant Do in the case of no phase transition; and the relationship between Q＊ and Q conforms to Q^＊=Q/A. Then, the new Arrhenius equation for AFHD is successfully constructed as Dz=Doexp[-Q/（ART）]. Meanwhile, the authentic equilibrium conformations at any dynamic moment can only be reproduced by the equilibration simulation of the HD-simulated configurations. Key words： accelerating factor method; Arrhenius equation; two-steps scheme; Mg/Zn interface; hyperdynamic simulation展开更多
The corrugated + flat rolling(CFR) and traditional rolling(TR) methods were used to prepare Mg/Al clad plates using AZ31 B Mg and 5052 Al plates, and the interface morphologies and mechanical properties of the resulti...The corrugated + flat rolling(CFR) and traditional rolling(TR) methods were used to prepare Mg/Al clad plates using AZ31 B Mg and 5052 Al plates, and the interface morphologies and mechanical properties of the resulting clad plates were compared. Examination of the microstructures of the plates showed that the TRed Mg/Al clad plate presented a straight interface, while a corrugated interface containing fractured intermetallic particulates was observed for the CFRed plate due to the inhomogeneous strain induced by the corrugated roller. During the CFR process, the corrugated roller can accelerate the rupture of the substrate work-hardening layers and facilitate the mutual extrusion of fresh metals to enhance the interface bonding. Compared with the traditional basal texture of the Mg alloy, the CFR process can change the texture morphology, thereby enhancing the plastic deformation ability of the Mg plate. Tensile tests showed that the CFRed Mg/Al clad plate exhibited a higher ultimate tensile strength(UTS, 316 MPa), which was~ 8% higher than that of the TRed plate(293 MPa). In addition, the bending curve of the CFRed clad plate was smooth and there was no stress sudden drop phenomenon in the bending process. The higher UTS and excellent bending properties of the CFRed clad plate could be attributed to the enhanced coordinated deformation ability of the substrates induced by the corrugated interface, grain refinement, and the change in the Mg alloy texture morphology.展开更多
Thickness of the intermetallic compounds(IMC)layer at the interface has a significant effect on the mechanical properties of Mg/Al dissimilar joints.However,the thickness of IMC layer can be only obtained by metallurg...Thickness of the intermetallic compounds(IMC)layer at the interface has a significant effect on the mechanical properties of Mg/Al dissimilar joints.However,the thickness of IMC layer can be only obtained by metallurgical microscopy,which is destructive and has to break down the weld.Therefore,it is crucial to find a reliable approach that can non-destructively predict the thickness of IMC layer in practical application.In the current study,Mg alloy and Al alloy were friction stir butt welded(FSW)under different tool rotation speeds(TRS)to obtain different thicknesses of IMC layers.As the TRS increased from 400 rpm to 1000 rpm,thickness of the IMC layer increased from 0.4μm to 1.3μm,the peak welding temperatures increased from 259℃to 402℃,and the Z-axis downforces decreased from10.5 kN to 3.2 k N during welding process.Higher TRS would generally induce higher welding heat input,which promotes the growth of the IMC layer and the softening of base materials.The IMC layer formed through solid-state diffusion and transformation instead of eutectic reaction according to the welding temperature history and interfacial microstructure,and its evolution process was clearly observed by plan view.In order to incorporate the effect of dramatic change of welding temperature which is the characteristic feature of FSW,Psd Voigt function was used to fit the welding temperature histories.A new prediction formula was then established to predict thicknesses of IMC layers with considering sharp welding temperature change.Predicted thicknesses gave good agreement with measured thicknesses obtained experimentally under different welding parameters,which confirmed the accuracy and reliability of the new prediction formula.Based on this prediction formula,the time period of temperature higher than 200℃during welding was found critical for the thickening of interfacial IMC layers.展开更多
Compound casting is an efficient method for bonding dissimilar metals,in which a dramatic reaction can occur between the melt and solid.The centrifugal casting process,a type of compound casting,was applied to cast Al...Compound casting is an efficient method for bonding dissimilar metals,in which a dramatic reaction can occur between the melt and solid.The centrifugal casting process,a type of compound casting,was applied to cast Al/Mg dissimilar bimetals.Magnesium melt was poured at 700 °C,with melt-to-solid volume ratios(Vm/Vs) of 1.5 and 3,into a preheated hollow aluminum cylinder.The preheating temperatures of the solid part were 320,400,and 450 °C,and the constant rotational speed was 1,600 rpm.The cast parts were kept inside the casting machine until reaching the cooling temperature of 150 °C.The result showed that an increase in preheating temperature from 320 to 450 °C led to an enhanced reaction layer thickness.In addition,an increase in the Vm/Vs from 1.5 to 3 resulted in raising the interface thickness from 1.2 to 1.8 mm.Moreover,the interface was not continuously formed when a Vm/Vs of 3 was selected.In this case,the force of contraction overcame the resultant acting force on the interface.An interface formed at the volume ratio of 1.5 was examined using scanning electron microscopy(SEM) equipped with energy-dispersive X-ray spectroscopy(EDS),and the results demonstrated the formation of Al_(3)Mg_(2),Al_(12)Mg_(17) and(δ+Al_(12)Mg_(17)) eutectic structures in the interface.展开更多
To improve the Al/Mg bimetallic interface,La was added into the Al/Mg bimetallic interface manufactured by a compound casting process.The effect of La addition on the microstructure,mechanical properties and fracture ...To improve the Al/Mg bimetallic interface,La was added into the Al/Mg bimetallic interface manufactured by a compound casting process.The effect of La addition on the microstructure,mechanical properties and fracture behavior of the Al/Mg bimetallic interface and the formation mechanism of the interface were studied in detail.Al_(11)La_(3),Al_(8)Mn_(4)La,Al_(20)Ti_(2)La,and other rare earth precipitates(RE precipitates)preferentially precipitated at the interface with La addition,while the number of the Al_(11)La_(3)and Al_(8)Mn_(4)La located in eutectic structure area(E area)gradually increased and aggregated in the interface with the increase of the La content.Besides,the matrix structure in different areas of the Al/Mg interface changed in different degrees,and the eutectic structure and primaryγ(Mg_(17)Al_(12))dendrites in the E area were refned,but the intermetallic compounds area(IMC area)had no obvious change.With the addition of the La,the interface was strengthened under the comprehensive effect of refnement strengthening and precipitation strengthening from the E area.When the La content increased to 1.0%,the shear strength of the Al/Mg bimetal reached the maximum of 51.54 MPa,which was 30.95%higher than the group without La addition.However,with the further increase of the La content,the large area aggregation of the Al_(11)La_(3)and Al_(8)Mn_(4)La occurred in the interface,leading to the separation of the matrix structure of the E area and the decrease of the shear strength of the Al/Mg interface.展开更多
Due to positive mixing heat between Fe and Mg,it is difficult to diffuse for Fe-Mg at the interface of steel/Mg laminated composites,resulting in the inability to achieve high-strength metallurgical bonding.In this pa...Due to positive mixing heat between Fe and Mg,it is difficult to diffuse for Fe-Mg at the interface of steel/Mg laminated composites,resulting in the inability to achieve high-strength metallurgical bonding.In this paper,20#steel/Mg laminated composites were prepared by large deformation rolling and subse-quent diffusion heat treatment process.The interfacial bonding strength was improved by constructing high-density crystal defects at the interface to promote element diffusion.The mechanisms of interface morphology evolution and element diffusion were analyzed by finite element simulation and theoretical calculation.The results show after diffusion heat treatment,the bond strength of the large deformation rolled interface was increased from 14 to 30 MPa.Fe-Mg transition layer with about 80 nm thickness as well as high-density vacancies,dislocations and grain boundaries were formed in the large deforma-tion rolled interface region.During diffusion heat treatment,Mg elements diffused into grain interior and grain boundary regions of 20#steel under the effect of heat-force coupling,and the thickness of Fe-Mg transition layer increased to 150 nm,forming an Fe-based supersaturated solid solution.The in-terface with high-density defects constituted a non-equilibrium interface.The 20#steel internal energy in the non-equilibrium interface is able to overcome positive mixing heat of immiscible Fe-Mg system and provide the driving force for Mg elements diffusion.Promoting elemental diffusion by constructing high-density defects can be a new concept to achieve metallurgical bonding at the interface of immiscible metal laminated composites.展开更多
Traditional rolled(TR)aluminum(Al)/magnesium(Mg)/aluminum(Al)composite plates have many bottlenecks such as multiple passes,low interlaminar strength,and weak mechanical properties.In this paper,the hard-plate rolling...Traditional rolled(TR)aluminum(Al)/magnesium(Mg)/aluminum(Al)composite plates have many bottlenecks such as multiple passes,low interlaminar strength,and weak mechanical properties.In this paper,the hard-plate rolling(HPR)method was used to prepare Al/Mg/Al composite plates under a single pass reduction of 60%.The results show that the ultimate tensile strength(UTS)of the composite plate obtained by hard-plate rolling is 262.3 MPa,and the percentage of total elongation at fracture(At)is 12.3%,which is 31.6%and 37.4%higher than that of the traditional rolling,respectively.It is attributed to the unique corrugated interlocking structure of the interface of the composite plate caused by hard-plate rolling.The shear texture produced by the Mg plate weakens the strong-basal texture.At the same time,the strong basal slip and the large amount of energy stored in the deformed grains provide favorable conditions for dynamic recrystallized(DRX)nucleation.The microstructure is deeply refined by DRX,and the strength and plasticity of the composite plate are improved synchronously.It provides scientific guidance for the development of high-performance lightweight composite plates and the research on hard-plate rolling technology and also has good industrial production and application potential.展开更多
In this study,the cold-spraying process was utilized to deposit Al particles onto an Al slab,an Mg slab,and both Al and Mg slabs to form an ultra-thin interlayer,and then the clad slabs were rolled at 400℃,developing...In this study,the cold-spraying process was utilized to deposit Al particles onto an Al slab,an Mg slab,and both Al and Mg slabs to form an ultra-thin interlayer,and then the clad slabs were rolled at 400℃,developing three roll-bonding processes:the roll-bonding process with cold-sprayed Al powder on the Al slab(CS-Al),the roll-bonding process with cold-sprayed Al powder on the Mg slab(CS-Mg),and the rollbonding process with cold-sprayed Al powder on both the Al slab and the Mg slab(CS-Both).The effects of three different cold-sprayed Al particle interlayer processes on the mechanical properties of rolled Mg/Al clad plates were investigated to improve the mechanical properties.The microstructure,texture evolution,intermetallic compound formation,mechanical properties,and mechanisms involved in the Mg/Al clad plate rolling were systematically investigated.The results showed that the pre-bonding between the particles and the substrates through coldspraying had a significant impact on the bonding strength of the Mg/Al clad plates,and the CS-Both process can increase the average shear strength of the Mg/Al clad plates to 49.24 MPa at a medium reduction rate of 37.5%,2.5 times that of the conventional rolling process.The CS-Both process constructed more evident dual microscopic three-dimensional interfaces and promoted more thorough atomic diffusion at the interface through the double-sided cold-spraying process.Meanwhile,the dual cold-sprayed Al coatings on both the Mg slab and Al slab underwent dynamic recrystallization during rolling to form a homogeneous unit with no additional coating interfaces.Fine grain strengthening and dislocation strengthening were judged to be important mechanisms for improving the mechanical performance of the interfacial layer.展开更多
Despite the advanced efficiency of perovskite solar cells(PSCs),electron transportation is still a pending issue.Here the polymer polyvinylpyrrolidone(PVP)is used to enhance the electron injection,which is thanks to t...Despite the advanced efficiency of perovskite solar cells(PSCs),electron transportation is still a pending issue.Here the polymer polyvinylpyrrolidone(PVP)is used to enhance the electron injection,which is thanks to the passivation of the defects at the interface between the ZnO electron transporting layer(ETL)and the perovskite.The application of the PVP layer inhibits the device degradation,and 80%of the primary efficiency is kept after 30 d storage in air condition.Additionally,the efficiency of the device is further enhanced by improving the conductivity and crystallinity of the ZnO ETL via Magnesium(Mg)doping in the ZnO nanorods(ZnO NRs).Moreover,the preparation parameters of the ZnO NRs are optimized.By employing the high-crystallinity ZnO ETL and the PVP layer,the power conversion efficiency(PCE)of the champion device is increased from 16.29%to 19.63%.These results demonstrate the advantages of combining mesoscale manipulation with interface modification and doping together.展开更多
Because the bonding interface of dissimilar metal joint between AZ31 B Mg alloy and DP600 galvanized steel by keyholeless friction stir spot welding(KFSSW)is permanent bonding,the interface morphology cannot be direct...Because the bonding interface of dissimilar metal joint between AZ31 B Mg alloy and DP600 galvanized steel by keyholeless friction stir spot welding(KFSSW)is permanent bonding,the interface morphology cannot be directly observed.If the joint is separated by external force,the original features of bonding interface of joint will be destroyed,which has influence on the accuracy for observation and analysis of the result.In this paper,the coordinates of the key point at the interface of every cross-section at intervals of 0.2 mm were measured and connected into an outline.The outline of all interfaces makes up the three-dimensional morphologies of bonding interface between AZ31 B Mg alloy and DP600 steel by KFSSW,which was constructed by Solidworks software to restore the real mechanical bonding state of joint.Combined with the microhardness analysis of cross-section and results of in-situ tensile test,the unique bonding state and morphology of Mg and steel in the welded joint were confirmed.展开更多
Fabricating Mg/Al laminate is an effective strategy to circumvent the inherently low formability and poor corrosion resistance of Mg alloys.Here,Mg/Al laminate with good bonding quality and mechanical properties was s...Fabricating Mg/Al laminate is an effective strategy to circumvent the inherently low formability and poor corrosion resistance of Mg alloys.Here,Mg/Al laminate with good bonding quality and mechanical properties was successfully fabricated via porthole die co-extrusion process using ZK60 Mg and TiB_(2)/6061Al composite as constituted layers.Integrating the results from microstructural characterization and mechanical testing,the effects of extrusion temperature on microstructure,interfacial structure,element diffusion,and mechanical properties were investigated.The results show that Mg/Al laminate achieves a sound welding quality by mechanical bonding and diffusion bonding.The obvious intermetallic compounds(βandγ)layer forms at Mg/Al interface,and its thickness increases to 8.3μm as the extrusion temperature reaches 400℃.High extrusion temperature promotes the dynamic recrystallization and grain growth of Mg and Al layers,while the dislocation density decreases.β/γinterface shows a coherent feature,whileγ/Mg interface is semi-coherent with a locally ordered transition zone of 4.5 nm.The rich Mg and Cr layers are found at TiB_(2)/6061 interface,which is conducive to improving the bonding quality.When the extrusion temperature is 370℃,the thickness of diffusion layer is around 5.0μm,and the bonding strength reaches 18.68 MPa,resulting in the best comprehensive mechanical properties.This work provides a new direction for the development of Mg/Al laminate with excellent strength and ductility.展开更多
In this work,Mg(0001)/AlB_(2)(0001)interfaces with various terminations and stacking orders were constructed,and the atomic and electronic structures and adhesion work(Wad)of the interface were investigated using the ...In this work,Mg(0001)/AlB_(2)(0001)interfaces with various terminations and stacking orders were constructed,and the atomic and electronic structures and adhesion work(Wad)of the interface were investigated using the first-principles calculations.Notably,during the geometry optimization process,the B-mid-top(B-MT)Mg(0001)/AlB_(2)(0001)interface exhibits the most significant interface changes and manifests the least stability.Horizontal movement of Mg atoms in the first layer of the Mg surface slab,along the normal direction,results in a structure akin to the structurally optimized hexagonal close-packed(HCP)interface.The B-HCP interface demonstrates the highest stability,the largest ideal Wad,and the smallest interface distance.The interface enhances the binding strength of the Mg-side sub-interface,but diminishes the binding strength of the AlB_(2)-side sub-interface.Furthermore,Mg atoms can form metallic/covalent mixed bonds with Al atoms on the Al-terminal AlB_(2) surface and form ionic bonds with B atoms on the B-terminal AlB_(2) surface.Mg(0001)/AlB_(2)(0001)interface has good bonding properties.This research provides strong theoretical support for an in-depth understanding of Mg/AlB_(2) interface characteristics.展开更多
The interfacial microstructures and configurations directly affect the comprehensive properties of the composites,but their interfacial adhesion mechanism is complicated to expound by experimental methods.In this work...The interfacial microstructures and configurations directly affect the comprehensive properties of the composites,but their interfacial adhesion mechanism is complicated to expound by experimental methods.In this work,based on the stacking sequence of the Mg/Mg_(2)Y interface models,nine different Mg/Mg_(2)Y interface configurations with top site,bridge site,and hollow site(HCP)under Mg1,Mg_(2),and Y terminations were successfully constructed and systematically explored by first-principles calculations.The results showed that the Mg_(2)Y(0001)surface with Y termination is the most stable when the yttrium chemical potential()is less than-1.09 eV;otherwise,Mg_(2)Y(0001)surface with Mg1 termination is the most stable.The seven-layer Mg(0001)and eleven-layer Mg_(2)Y(0001)slabs are employed to reflect the bulk-like interior properties.Additionally,the Mg(0001)/Mg_(2)Y(0001)with the Y-HCP stacking has the largest interface thermodynamic stability with the value of 2.383 J/m^(2) in all interface configurations owing to its largest work of adhesion.In addition,the interfacial energy of Y-HCP stacking is significantly smaller than those of Mg1-HCP when is approximately less than-0.55 eV,showing that it is more stable.The thermodynamic stability of Mg/Mg_(2)Y with Y-HCP is due to Mg-Y chemical bonds formed between Mg and Y atoms.Lastly,the Mg/Mg_(2)Y interfaces are strong interfaces based on the Griffith fracture theory.展开更多
The interfaces between in-situ Al3Ti particles and magnesium(Mg)matrix are crucial role in highperformance titanium(Ti)reinforced AZ31 alloy.Herein,the interfaces between Al3Ti particles and the Mg matrix are fabricat...The interfaces between in-situ Al3Ti particles and magnesium(Mg)matrix are crucial role in highperformance titanium(Ti)reinforced AZ31 alloy.Herein,the interfaces between Al3Ti particles and the Mg matrix are fabricated and investigated using advanced characterization tools and first-principles calculations.The orientation relationship(OR)and atomic interface structure between the Al_(3)Ti particles and matrix are characterized using a high-resolution transmission electron microscope.The OR is determined to be(1010)Mg//(001)Al3Ti;[1213]Mg//[100]Al3Ti.Based on the characterized OR,the interface properties(including atomic structure,work of adhesion,interface energy,and fracture mechanism)are investigated using first-principles calculations.The relaxed interface structure indicates that the TiAl-terminated bridge site configurations(MT1)and hollow site configurations(HCP1)are unstable and would convert into other bridge site configurations(MT).Furthermore,the work of adhesion and interface energy suggests that Al-terminated hollow site configurations(HCP)and bridge site configurations(MT)are more stable than other configurations.In addition,the calculations of work of fracture show that fracture of the interfaces with Al-MT1,Al-HCP,and TiAl-MT configurations may initiate from bulk Mg interior.The findings may help to understand and tailor the deformation mechanisms and mechanical properties of Ti-reinforced Mg alloys.展开更多
A model Cu-AlN composite has been prepared by ion implantation technique and annealing. The atomic configuration and lattice relationship of a low-energy inherent interface(11)Cn//(0001)AlN were studied by using trans...A model Cu-AlN composite has been prepared by ion implantation technique and annealing. The atomic configuration and lattice relationship of a low-energy inherent interface(11)Cn//(0001)AlN were studied by using transmission electron microscopy and geometrical modelling. By analysing the dichromatic pattern of the composite,a primary structural unit of the interface atomic configuration was determined for purpose of HREM image simulations and of studying the structurul relaxation state in the near-interface region.展开更多
To understand the interface characteristics between the precipitateβ2'and the Mg matrix,and thus guide the development of new Mg-Zn alloys,we investigated the atomic interface structure,work of adhesion(Wad),and ...To understand the interface characteristics between the precipitateβ2'and the Mg matrix,and thus guide the development of new Mg-Zn alloys,we investigated the atomic interface structure,work of adhesion(Wad),and interfacial energy(γ)of Mg(0001)/β2’(MgZn_(2))(0001)interface,as well as the effect of segregation behavior of the introduced transition metal atoms(3d,4d and 5d)on interfacial bonding strength.The calculated works of adhesion and interfacial energies dementated that the Zn2-terminated MT+HCP configuration is the most stable structure for all considered models.Take the Zn2-MT+HCP interface as the research object,estimated segregated energies(Eseg)reveal that added transition metal atoms prefer to segregate at Mg-I and Mg-II sites.The predicted Wad and charge density difference results reveal that the segregation of alloying additives employed may all strengthen Mg(0001)/MgZn_(2)(0001)interface,with the enhancement effect of Os,Re,Tc,W,and Ru at the Mg-II site being the most pronounced.展开更多
基金supported by Guangdong Major Project of Basic and Applied Basic Research, China (No. 2020B0301030006)Fundamental Research Funds for the Central Universities, China (No. SWU-XDJH202313)+1 种基金Chongqing Postdoctoral Science Foundation Funded Project, China (No. 2112012728014435)the Chongqing Postgraduate Research and Innovation Project, China (No. CYS23197)。
文摘A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The results show that cold-pressing produces intense plastic deformation near the corrugated surface of the Al plate,which promotes dynamic recrystallization of the Al substrate near the interface during the subsequent hot-pressing.In addition,the initial corrugation on the surface of the Al plate also changes the local stress state near the interface during hot pressing,which has a large effect on the texture components of the substrates near the corrugated interface.The construction of the corrugated interface can greatly enhance the shear strength by 2−4 times due to the increased contact area and the strong“mechanical gearing”effect.Moreover,the mechanical properties are largely depended on the orientation relationship between corrugated direction and loading direction.
基金financially supported by the National Natural Science Foundation of China(Nos.52175444,51905506,21871065 and 22071038)the Sichuan Science and Technology Program(No.2021JDJQ0014).
文摘Additive manufacturing(AM)methods have garnered considerable attention owing to their flexibility in fabricating complex parts with desirable mechanical properties.However,the poor surface quality of the resulting metal parts remains a severe challenge for the applications.Here,a novel dual-additive synergy strategy is presented,which simultaneously enhances material removal efficiency and regulates electrode surface reactions during electrochemical polishing(ECP)of AM AlSi10Mg.Theoretical studies and experimental characterizations confirm that NaF promotes selective dissolution at the peaks,while glucose acts as a stabilizer for the surface valleys.This approach effectively facilitates the selective removal of surface protrusions,achieving a smoother and more uniform surface finish,resulting in a surface roughness reduction of approximately 86%,compared to a 63%reduction without additives.This study not only provides a new approach for optimizing surface quality of AM AlSi10Mg but also offers new insights into electrolyte design and the stabilization of metal anodes.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030006)the Guangdong Basic and Applied Basic Research Foundation[Grant No.2021B1515120071]+1 种基金R.Shi would like to thank the financial support from the open research fund of Songshan Lake Materials Laboratory(2021SLABFK06)start-up funding from Harbin Institute of Technology(Shenzhen).
文摘Magnesium alloys have gained extensive applications across various industries,including aerospace,transportation,and civil construction,owing to their excellent combinations of high specific strength and stiffness[1].However,their lim-ited strength due to the lack of effective strengthening phases has hindered their broader industrial applications[2].Never-theless,it has been challenging to achieve significant strength-ening due to the restricted solubility of alloying elements in magnesium[3].Thus,more and more efforts have been made to explore the concept of secondary phase-reinforced magne-sium alloys[2,4,5],where the secondary phase acts as re-inforcing agents within the magnesium matrix,resembling a composite material.
基金Project (2012CB722805) supported by the National Basic Research Program of ChinaProjects (50974083, 51174131) supported by the National Natural Science Foundation of China+1 种基金Project (50774112) supported by the Joint Fund of NSFC and Baosteel, ChinaProject(07QA4021) supported by the Shanghai "Phosphor" Science Foundation, China
文摘The accelerating factor （AF） method is a simple and appropriate way to investigate the atomic long-time deep diffusion at solid-solid interface. In the framework of AF hyperdynamics （HD） simulation, the relationship between the diffusion coefficient along the direction of z-axis which is normal to the Mg/Zn interface and temperature was investigated, and the AF＇s impact on the diffusion constant （D0） and activation energy （Q^＊） was studied. Then, two steps were taken to simulate the atomic diffusion process and the formation of new phases： one for acceleration and the other for equilibration. The results show that： the Arrhenius equation works well for the description of Dz with different accelerating factors; the AF has no effect on the diffusion constant Do in the case of no phase transition; and the relationship between Q＊ and Q conforms to Q^＊=Q/A. Then, the new Arrhenius equation for AFHD is successfully constructed as Dz=Doexp[-Q/（ART）]. Meanwhile, the authentic equilibrium conformations at any dynamic moment can only be reproduced by the equilibration simulation of the HD-simulated configurations. Key words： accelerating factor method; Arrhenius equation; two-steps scheme; Mg/Zn interface; hyperdynamic simulation
基金financially supported by the National Natural Science Foundation of China(Nos.U1710254,51904205,51904206)Science and Technology Foundation of State Key laboratory(No.6142909180205)+4 种基金Taiyuan City Science and Technology Major Projects(No.170203)Shanxi Province Science and Technology Major Projects(Nos.MC2016-01,20181101008)the Natural Science Foundation of Shanxi Province(Nos.201801D221221,201801D221130 and 201801D221346)Key Projects of Shanxi Province Key Research and Development Plan(No.201703D111003)the China Postdoctoral Science Foundation(Nos.2018M641680,2018M641681)。
文摘The corrugated + flat rolling(CFR) and traditional rolling(TR) methods were used to prepare Mg/Al clad plates using AZ31 B Mg and 5052 Al plates, and the interface morphologies and mechanical properties of the resulting clad plates were compared. Examination of the microstructures of the plates showed that the TRed Mg/Al clad plate presented a straight interface, while a corrugated interface containing fractured intermetallic particulates was observed for the CFRed plate due to the inhomogeneous strain induced by the corrugated roller. During the CFR process, the corrugated roller can accelerate the rupture of the substrate work-hardening layers and facilitate the mutual extrusion of fresh metals to enhance the interface bonding. Compared with the traditional basal texture of the Mg alloy, the CFR process can change the texture morphology, thereby enhancing the plastic deformation ability of the Mg plate. Tensile tests showed that the CFRed Mg/Al clad plate exhibited a higher ultimate tensile strength(UTS, 316 MPa), which was~ 8% higher than that of the TRed plate(293 MPa). In addition, the bending curve of the CFRed clad plate was smooth and there was no stress sudden drop phenomenon in the bending process. The higher UTS and excellent bending properties of the CFRed clad plate could be attributed to the enhanced coordinated deformation ability of the substrates induced by the corrugated interface, grain refinement, and the change in the Mg alloy texture morphology.
基金supported by the National Natural Science Foundation of China(No.52075330)the Interdisciplinary Program of Shanghai Jiao Tong University(No.YG2019QNA15)the Foundation of National Facility for Translational Medicine(Shanghai)(No.TMSK-2020-107)。
文摘Thickness of the intermetallic compounds(IMC)layer at the interface has a significant effect on the mechanical properties of Mg/Al dissimilar joints.However,the thickness of IMC layer can be only obtained by metallurgical microscopy,which is destructive and has to break down the weld.Therefore,it is crucial to find a reliable approach that can non-destructively predict the thickness of IMC layer in practical application.In the current study,Mg alloy and Al alloy were friction stir butt welded(FSW)under different tool rotation speeds(TRS)to obtain different thicknesses of IMC layers.As the TRS increased from 400 rpm to 1000 rpm,thickness of the IMC layer increased from 0.4μm to 1.3μm,the peak welding temperatures increased from 259℃to 402℃,and the Z-axis downforces decreased from10.5 kN to 3.2 k N during welding process.Higher TRS would generally induce higher welding heat input,which promotes the growth of the IMC layer and the softening of base materials.The IMC layer formed through solid-state diffusion and transformation instead of eutectic reaction according to the welding temperature history and interfacial microstructure,and its evolution process was clearly observed by plan view.In order to incorporate the effect of dramatic change of welding temperature which is the characteristic feature of FSW,Psd Voigt function was used to fit the welding temperature histories.A new prediction formula was then established to predict thicknesses of IMC layers with considering sharp welding temperature change.Predicted thicknesses gave good agreement with measured thicknesses obtained experimentally under different welding parameters,which confirmed the accuracy and reliability of the new prediction formula.Based on this prediction formula,the time period of temperature higher than 200℃during welding was found critical for the thickening of interfacial IMC layers.
文摘Compound casting is an efficient method for bonding dissimilar metals,in which a dramatic reaction can occur between the melt and solid.The centrifugal casting process,a type of compound casting,was applied to cast Al/Mg dissimilar bimetals.Magnesium melt was poured at 700 °C,with melt-to-solid volume ratios(Vm/Vs) of 1.5 and 3,into a preheated hollow aluminum cylinder.The preheating temperatures of the solid part were 320,400,and 450 °C,and the constant rotational speed was 1,600 rpm.The cast parts were kept inside the casting machine until reaching the cooling temperature of 150 °C.The result showed that an increase in preheating temperature from 320 to 450 °C led to an enhanced reaction layer thickness.In addition,an increase in the Vm/Vs from 1.5 to 3 resulted in raising the interface thickness from 1.2 to 1.8 mm.Moreover,the interface was not continuously formed when a Vm/Vs of 3 was selected.In this case,the force of contraction overcame the resultant acting force on the interface.An interface formed at the volume ratio of 1.5 was examined using scanning electron microscopy(SEM) equipped with energy-dispersive X-ray spectroscopy(EDS),and the results demonstrated the formation of Al_(3)Mg_(2),Al_(12)Mg_(17) and(δ+Al_(12)Mg_(17)) eutectic structures in the interface.
基金the supports provided by the National Natural Science Foundation of China(No.52075198)the National Key Research and Development Program of China(No.2020YFB2008304)+1 种基金the State Key Lab of Advanced Metals and Materials(No.2021-ZD07)the Analytical and Testing Center,HUST。
文摘To improve the Al/Mg bimetallic interface,La was added into the Al/Mg bimetallic interface manufactured by a compound casting process.The effect of La addition on the microstructure,mechanical properties and fracture behavior of the Al/Mg bimetallic interface and the formation mechanism of the interface were studied in detail.Al_(11)La_(3),Al_(8)Mn_(4)La,Al_(20)Ti_(2)La,and other rare earth precipitates(RE precipitates)preferentially precipitated at the interface with La addition,while the number of the Al_(11)La_(3)and Al_(8)Mn_(4)La located in eutectic structure area(E area)gradually increased and aggregated in the interface with the increase of the La content.Besides,the matrix structure in different areas of the Al/Mg interface changed in different degrees,and the eutectic structure and primaryγ(Mg_(17)Al_(12))dendrites in the E area were refned,but the intermetallic compounds area(IMC area)had no obvious change.With the addition of the La,the interface was strengthened under the comprehensive effect of refnement strengthening and precipitation strengthening from the E area.When the La content increased to 1.0%,the shear strength of the Al/Mg bimetal reached the maximum of 51.54 MPa,which was 30.95%higher than the group without La addition.However,with the further increase of the La content,the large area aggregation of the Al_(11)La_(3)and Al_(8)Mn_(4)La occurred in the interface,leading to the separation of the matrix structure of the E area and the decrease of the shear strength of the Al/Mg interface.
基金supported by the National Key R&D Program of China (No.2018YFA0707300).
文摘Due to positive mixing heat between Fe and Mg,it is difficult to diffuse for Fe-Mg at the interface of steel/Mg laminated composites,resulting in the inability to achieve high-strength metallurgical bonding.In this paper,20#steel/Mg laminated composites were prepared by large deformation rolling and subse-quent diffusion heat treatment process.The interfacial bonding strength was improved by constructing high-density crystal defects at the interface to promote element diffusion.The mechanisms of interface morphology evolution and element diffusion were analyzed by finite element simulation and theoretical calculation.The results show after diffusion heat treatment,the bond strength of the large deformation rolled interface was increased from 14 to 30 MPa.Fe-Mg transition layer with about 80 nm thickness as well as high-density vacancies,dislocations and grain boundaries were formed in the large deforma-tion rolled interface region.During diffusion heat treatment,Mg elements diffused into grain interior and grain boundary regions of 20#steel under the effect of heat-force coupling,and the thickness of Fe-Mg transition layer increased to 150 nm,forming an Fe-based supersaturated solid solution.The in-terface with high-density defects constituted a non-equilibrium interface.The 20#steel internal energy in the non-equilibrium interface is able to overcome positive mixing heat of immiscible Fe-Mg system and provide the driving force for Mg elements diffusion.Promoting elemental diffusion by constructing high-density defects can be a new concept to achieve metallurgical bonding at the interface of immiscible metal laminated composites.
基金supported by the Key Laboratory of Micro-systems and Micro-structures Manufacturing of Ministry of Education,Harbin Institute of Technology(2020KM005).
文摘Traditional rolled(TR)aluminum(Al)/magnesium(Mg)/aluminum(Al)composite plates have many bottlenecks such as multiple passes,low interlaminar strength,and weak mechanical properties.In this paper,the hard-plate rolling(HPR)method was used to prepare Al/Mg/Al composite plates under a single pass reduction of 60%.The results show that the ultimate tensile strength(UTS)of the composite plate obtained by hard-plate rolling is 262.3 MPa,and the percentage of total elongation at fracture(At)is 12.3%,which is 31.6%and 37.4%higher than that of the traditional rolling,respectively.It is attributed to the unique corrugated interlocking structure of the interface of the composite plate caused by hard-plate rolling.The shear texture produced by the Mg plate weakens the strong-basal texture.At the same time,the strong basal slip and the large amount of energy stored in the deformed grains provide favorable conditions for dynamic recrystallized(DRX)nucleation.The microstructure is deeply refined by DRX,and the strength and plasticity of the composite plate are improved synchronously.It provides scientific guidance for the development of high-performance lightweight composite plates and the research on hard-plate rolling technology and also has good industrial production and application potential.
基金funded by the National Natural Science Foundation of China(Grant No.52305405,52075359)the Natural Science Foundation Research Program of Shanxi Province(Grant No.202203021222121)+1 种基金the Fund for Shanxi“1331Project”Key Innovative Research Teamthe Chinese Postdoctoral Science Foundation(Grant No.2021M702544)。
文摘In this study,the cold-spraying process was utilized to deposit Al particles onto an Al slab,an Mg slab,and both Al and Mg slabs to form an ultra-thin interlayer,and then the clad slabs were rolled at 400℃,developing three roll-bonding processes:the roll-bonding process with cold-sprayed Al powder on the Al slab(CS-Al),the roll-bonding process with cold-sprayed Al powder on the Mg slab(CS-Mg),and the rollbonding process with cold-sprayed Al powder on both the Al slab and the Mg slab(CS-Both).The effects of three different cold-sprayed Al particle interlayer processes on the mechanical properties of rolled Mg/Al clad plates were investigated to improve the mechanical properties.The microstructure,texture evolution,intermetallic compound formation,mechanical properties,and mechanisms involved in the Mg/Al clad plate rolling were systematically investigated.The results showed that the pre-bonding between the particles and the substrates through coldspraying had a significant impact on the bonding strength of the Mg/Al clad plates,and the CS-Both process can increase the average shear strength of the Mg/Al clad plates to 49.24 MPa at a medium reduction rate of 37.5%,2.5 times that of the conventional rolling process.The CS-Both process constructed more evident dual microscopic three-dimensional interfaces and promoted more thorough atomic diffusion at the interface through the double-sided cold-spraying process.Meanwhile,the dual cold-sprayed Al coatings on both the Mg slab and Al slab underwent dynamic recrystallization during rolling to form a homogeneous unit with no additional coating interfaces.Fine grain strengthening and dislocation strengthening were judged to be important mechanisms for improving the mechanical performance of the interfacial layer.
基金Project supported by Beijing Natural Science Foundation,China(Grant No.2202030)the National Natural Science Foundation of China(Grant No.41422050303)+1 种基金the Program of Introducing Talents of Discipline to Universities(Grant No.B14003)the Fundamental Research Funds for Central Universities,China(Grant Nos.FRF-GF-19-001A and FRF-GF-19-002B).
文摘Despite the advanced efficiency of perovskite solar cells(PSCs),electron transportation is still a pending issue.Here the polymer polyvinylpyrrolidone(PVP)is used to enhance the electron injection,which is thanks to the passivation of the defects at the interface between the ZnO electron transporting layer(ETL)and the perovskite.The application of the PVP layer inhibits the device degradation,and 80%of the primary efficiency is kept after 30 d storage in air condition.Additionally,the efficiency of the device is further enhanced by improving the conductivity and crystallinity of the ZnO ETL via Magnesium(Mg)doping in the ZnO nanorods(ZnO NRs).Moreover,the preparation parameters of the ZnO NRs are optimized.By employing the high-crystallinity ZnO ETL and the PVP layer,the power conversion efficiency(PCE)of the champion device is increased from 16.29%to 19.63%.These results demonstrate the advantages of combining mesoscale manipulation with interface modification and doping together.
基金supported by Natural Science Foundation of Shandong Province(No.ZR2019PEE042)。
文摘Because the bonding interface of dissimilar metal joint between AZ31 B Mg alloy and DP600 galvanized steel by keyholeless friction stir spot welding(KFSSW)is permanent bonding,the interface morphology cannot be directly observed.If the joint is separated by external force,the original features of bonding interface of joint will be destroyed,which has influence on the accuracy for observation and analysis of the result.In this paper,the coordinates of the key point at the interface of every cross-section at intervals of 0.2 mm were measured and connected into an outline.The outline of all interfaces makes up the three-dimensional morphologies of bonding interface between AZ31 B Mg alloy and DP600 steel by KFSSW,which was constructed by Solidworks software to restore the real mechanical bonding state of joint.Combined with the microhardness analysis of cross-section and results of in-situ tensile test,the unique bonding state and morphology of Mg and steel in the welded joint were confirmed.
基金supports from the National Natural Science Foundation of China(52175338 and 52222510)Science Fund for Distinguished Young Scholars of Shandong Province(ZR2021JQ21)Key Research and Development Program of Shandong Province(2021ZLGX01).
文摘Fabricating Mg/Al laminate is an effective strategy to circumvent the inherently low formability and poor corrosion resistance of Mg alloys.Here,Mg/Al laminate with good bonding quality and mechanical properties was successfully fabricated via porthole die co-extrusion process using ZK60 Mg and TiB_(2)/6061Al composite as constituted layers.Integrating the results from microstructural characterization and mechanical testing,the effects of extrusion temperature on microstructure,interfacial structure,element diffusion,and mechanical properties were investigated.The results show that Mg/Al laminate achieves a sound welding quality by mechanical bonding and diffusion bonding.The obvious intermetallic compounds(βandγ)layer forms at Mg/Al interface,and its thickness increases to 8.3μm as the extrusion temperature reaches 400℃.High extrusion temperature promotes the dynamic recrystallization and grain growth of Mg and Al layers,while the dislocation density decreases.β/γinterface shows a coherent feature,whileγ/Mg interface is semi-coherent with a locally ordered transition zone of 4.5 nm.The rich Mg and Cr layers are found at TiB_(2)/6061 interface,which is conducive to improving the bonding quality.When the extrusion temperature is 370℃,the thickness of diffusion layer is around 5.0μm,and the bonding strength reaches 18.68 MPa,resulting in the best comprehensive mechanical properties.This work provides a new direction for the development of Mg/Al laminate with excellent strength and ductility.
基金supported by the Innovation Team Cultivation Project of Yunnan Province under Grant No.202005AE160016the Key Research&Development Program of Yunnan Province under Grant No.202103AA080017.
文摘In this work,Mg(0001)/AlB_(2)(0001)interfaces with various terminations and stacking orders were constructed,and the atomic and electronic structures and adhesion work(Wad)of the interface were investigated using the first-principles calculations.Notably,during the geometry optimization process,the B-mid-top(B-MT)Mg(0001)/AlB_(2)(0001)interface exhibits the most significant interface changes and manifests the least stability.Horizontal movement of Mg atoms in the first layer of the Mg surface slab,along the normal direction,results in a structure akin to the structurally optimized hexagonal close-packed(HCP)interface.The B-HCP interface demonstrates the highest stability,the largest ideal Wad,and the smallest interface distance.The interface enhances the binding strength of the Mg-side sub-interface,but diminishes the binding strength of the AlB_(2)-side sub-interface.Furthermore,Mg atoms can form metallic/covalent mixed bonds with Al atoms on the Al-terminal AlB_(2) surface and form ionic bonds with B atoms on the B-terminal AlB_(2) surface.Mg(0001)/AlB_(2)(0001)interface has good bonding properties.This research provides strong theoretical support for an in-depth understanding of Mg/AlB_(2) interface characteristics.
基金supported by the National Natural Science Foundation of China (No.52225101)the Central Universities of China (2021CDJQY-040)+2 种基金the Guangdong Major Project of Basic and Applied Basic Research (2020B0301030006)the Independent Research Project of State Key Laboratory of Mechanical Transmissions (SKLMT-ZZKT-2022Z01,SKLMT-ZZKT-2022M12)the Chongqing Special Project of Science and Technology Innovation of China (cstc2021yszx-jcyj0007).
文摘The interfacial microstructures and configurations directly affect the comprehensive properties of the composites,but their interfacial adhesion mechanism is complicated to expound by experimental methods.In this work,based on the stacking sequence of the Mg/Mg_(2)Y interface models,nine different Mg/Mg_(2)Y interface configurations with top site,bridge site,and hollow site(HCP)under Mg1,Mg_(2),and Y terminations were successfully constructed and systematically explored by first-principles calculations.The results showed that the Mg_(2)Y(0001)surface with Y termination is the most stable when the yttrium chemical potential()is less than-1.09 eV;otherwise,Mg_(2)Y(0001)surface with Mg1 termination is the most stable.The seven-layer Mg(0001)and eleven-layer Mg_(2)Y(0001)slabs are employed to reflect the bulk-like interior properties.Additionally,the Mg(0001)/Mg_(2)Y(0001)with the Y-HCP stacking has the largest interface thermodynamic stability with the value of 2.383 J/m^(2) in all interface configurations owing to its largest work of adhesion.In addition,the interfacial energy of Y-HCP stacking is significantly smaller than those of Mg1-HCP when is approximately less than-0.55 eV,showing that it is more stable.The thermodynamic stability of Mg/Mg_(2)Y with Y-HCP is due to Mg-Y chemical bonds formed between Mg and Y atoms.Lastly,the Mg/Mg_(2)Y interfaces are strong interfaces based on the Griffith fracture theory.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030006)the financial support from the open research fund of Songshan Lake Materials Laboratory(2021SLABFK06)and start-up funding from Harbin Institute of Technology(Shenzhen).
文摘The interfaces between in-situ Al3Ti particles and magnesium(Mg)matrix are crucial role in highperformance titanium(Ti)reinforced AZ31 alloy.Herein,the interfaces between Al3Ti particles and the Mg matrix are fabricated and investigated using advanced characterization tools and first-principles calculations.The orientation relationship(OR)and atomic interface structure between the Al_(3)Ti particles and matrix are characterized using a high-resolution transmission electron microscope.The OR is determined to be(1010)Mg//(001)Al3Ti;[1213]Mg//[100]Al3Ti.Based on the characterized OR,the interface properties(including atomic structure,work of adhesion,interface energy,and fracture mechanism)are investigated using first-principles calculations.The relaxed interface structure indicates that the TiAl-terminated bridge site configurations(MT1)and hollow site configurations(HCP1)are unstable and would convert into other bridge site configurations(MT).Furthermore,the work of adhesion and interface energy suggests that Al-terminated hollow site configurations(HCP)and bridge site configurations(MT)are more stable than other configurations.In addition,the calculations of work of fracture show that fracture of the interfaces with Al-MT1,Al-HCP,and TiAl-MT configurations may initiate from bulk Mg interior.The findings may help to understand and tailor the deformation mechanisms and mechanical properties of Ti-reinforced Mg alloys.
文摘A model Cu-AlN composite has been prepared by ion implantation technique and annealing. The atomic configuration and lattice relationship of a low-energy inherent interface(11)Cn//(0001)AlN were studied by using transmission electron microscopy and geometrical modelling. By analysing the dichromatic pattern of the composite,a primary structural unit of the interface atomic configuration was determined for purpose of HREM image simulations and of studying the structurul relaxation state in the near-interface region.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030006)National Natural Science Foundation of China[Grant No.51871077]+2 种基金Shenzhen Knowledge Inno-vation Plan-Fundamental Research(Discipline Distribu-tion)[Grant No.JCYJ20180507184623297]Shenzhen Sci-ence and Technology Plan-Technology Innovation[Grant No.KQJSCX20180328165656256]Startup Foundation from Shenzhen and Startup Foundation from Harbin Institute of Technology(Shenzhen).
文摘To understand the interface characteristics between the precipitateβ2'and the Mg matrix,and thus guide the development of new Mg-Zn alloys,we investigated the atomic interface structure,work of adhesion(Wad),and interfacial energy(γ)of Mg(0001)/β2’(MgZn_(2))(0001)interface,as well as the effect of segregation behavior of the introduced transition metal atoms(3d,4d and 5d)on interfacial bonding strength.The calculated works of adhesion and interfacial energies dementated that the Zn2-terminated MT+HCP configuration is the most stable structure for all considered models.Take the Zn2-MT+HCP interface as the research object,estimated segregated energies(Eseg)reveal that added transition metal atoms prefer to segregate at Mg-I and Mg-II sites.The predicted Wad and charge density difference results reveal that the segregation of alloying additives employed may all strengthen Mg(0001)/MgZn_(2)(0001)interface,with the enhancement effect of Os,Re,Tc,W,and Ru at the Mg-II site being the most pronounced.
