Solute Drag Effect Research Articles

Microstructure and mechanical properties of Nb microalloyed high‑carbon pearlitic steels subjected to isothermal transformation

Niobium (Nb) is mainly added to low-carbon steels, in which the main microstructure is ferrite and/or bainite, to refine grains and improve their properties. However, the studies on Nb in high-carbon pearlitic steels are insufficient, and there are some debates regarding the existing studies. High-carbon pearlitic steel is widely used in bars, wires, and steel rails. The role of Nb in high-carbon steels may differ for different steel grades and under different heat treatments. Hence, further detailed studies are required to improve the properties of high-carbon pearlitic steels. In this study, two series of high-carbon pearlitic steels (68C and 75C series) were designed and subjected to isothermal pearlite transformation at different austenitization and isothermal transformation temperatures. The microstructures and mechanical properties of the steels were investigated by optical microscopy, field-emission scanning electron microscopy, electron backscatter diffraction, scanning transmission electron microscopy, and hardness tests. The results showed that the pearlite lamellae were refined by the addition of Nb to high-carbon pearlitic steels, which was attributed to the solute drag effect of Nb. The pearlite colony and nodule sizes also became finer with the addition of Nb because of the finer prior austenite grains and smaller pearlite growth rates. However, the refinement of the pearlite lamellae, nodules, and colonies by the addition of Nb was not significantly enhanced by increasing the Nb content from 0.014 wt% to 0.027 wt% in 75C series samples. In addition, the pearlite interlamellar spacing and colony and nodule sizes of the samples decreased with decreasing isothermal and austenitization temperatures. Moreover, the addition of Nb to high-carbon steels increased their hardness and yield strength. The main strengthening mechanisms of Nb in high-carbon steel are grain refinement strengthening and precipitation strengthening in the samples austenitized at 900 °C, whereas the improvement of strength is mainly attributed to grain refinement strengthening in the samples austenitized at 1180 °C. This study systematically characterized the pearlite morphology of Nb microalloyed high-carbon steels and analyzed the strengthening mechanism, providing a theoretical reference for the development of Nb-containing high-carbon pearlitic steels.

The recrystallization, texture and mechanical behavior of hot rolled and annealed Mg-10Ho binary alloy

The recrystallization, texture, and mechanical properties of hot-rolled and hot-rolled + annealed Mg-10Ho (wt %) are investigated. Mg-10Ho binary alloy is first solution treated followed by multipass rolling at 420 °C for up to 50 % reduction and subsequently annealed at 400 °C for different times for up to 60 min. The microstructure of deformed and annealed samples was characterized using a field-emission secondary electron microscope (FESEM) and electron back-scattered diffraction (EBSD) and the mechanical properties were examined using hardness and tensile tests. The as-rolled microstructure contains fine dynamic recrystallized grains and different types of deformation twins. With increasing annealing time, a decrease in the hardness was observed, suggesting initiation of recovery and static recrystallization. After 10 min of annealing, an equiaxed, nearly fully recrystallized microstructure with a grain size of 14 µm and weaker basal texture was obtained. This annealed sample exhibits an ultimate tensile strength of 213 MPa, yield strength of 145 MPa, and ductility of ∼7 %. Such an optimum combination of strength and ductility is attributed to the combined effect of solid solution strengthening, grain refinement, and texture weakening. Additionally, the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model was used to understand the recrystallization kinetics of Mg-10Ho and compared it with that of Mg-10Y. Results indicate that the solute drag effect plays a dominant role in the faster recrystallization kinetics of Mg-10Ho alloy. Finally, the texture variation in Mg-10Ho and Mg-10Y is also explained based on the solute drag effect.

Microstructures in a carburized steel after isothermal pearlitic treatment

The influence of carbon concentration variations on pearlite formation (20 h at 600 °C) in a case-carburized steel is investigated. The resultant microstructure shows three distinct regions: carburized case, a transition region, and the original core. The microstructural transition from the case to the core regions is observed to be relatively sharp. The investigated region of the carburized case (0.9 wt.% C) contains two types of pearlite: ferrite + cementite and ferrite + M23C6, where the pearlitic aggregate with M23C6 shows faster formation kinetics. The kinetics of pearlite formation in the transition region (0.3 wt.% C) is very slow and is observed with only M23C6 carbide. Only around 40% austenite decomposes into pearlite in the transition region, which, in comparison to the carburized case region of 0.9 wt.% C is a fraction that is lower by a factor of two. Pearlite is absent in the investigated core region (0.16 wt.% C). The microstructure in this region is predominantly martensite and pro-eutectoid ferrite, with a fraction of ferrite well below the equilibrium fraction. Ferrite formation in this region is limited by the redistribution of mainly Ni, Mn, and Cr, and their resulting solute drag effect on the austenite/ferrite interface. A thermodynamic and kinetic argumentation of these observations is provided with the help of thermodynamic data, precipitation simulations, and a general mixed-mode Gibbs energy balance model.

Abnormal grain growth under solution-aging treatments enables convergence mechanical properties of a Fe-Ni-Cr based austenitic alloy

In this study, systematic heat treatment routes including solution (980 °C to 1130 °C) and aging (675 °C to 775 °C) processes were used to tailor the microstructural evolution and mechanical performance of a Fe-Ni-Cr based austenitic alloy, strengthened by a γ′ phase (Ni3(Ti, Al)). Grain growth was observed with increasing solution treatment temperature from nearly 90 μm (980 °C) to nearly 200 μm (1130 °C). Grain refinement during solution heat processes was found to ascribe to the solute drag effect and the pinning effect of nickel-titanium-enriched segregates and precipitates. During aging, the precipitation behavior of γ′ is found to be almost independent of solution treatment temperatures. Interestingly, abnormal grain growth during aging was observed. The motion of grain boundaries was ascribed to the formation of nickel-titanium-enriched γ′ in the austenitic matrix, thereby contributing to the dissolution of the previously enriched segregates and precipitates from grain boundaries. The studied alloy shows a wide range of mechanical properties, from tensile strength of 1131 MPa with ductility at 36%, to tensile strength of 880 MPa with ductility at 50%. The current study demonstrates that grain refinement of the alloy at solution treatment may not benefit the final mechanical properties.

Growth kinetics of the sputtered Ni-30Cr-5Al alloy nanograins: Effects of Y addition and oxidation

The grain growth of the sputtered Ni-30Cr-5Al and Ni-30Cr-5Al-1Y (wt%) nanocrystalline alloys during temperature rising to and isothermally holding at 1000 °C in Ar has been investigated by transmission electron microscope (TEM). The thermal-induced grain growth of the two alloys at 1000 °C follows a law of dn − d0n = kt but the Y presence results in an increase of n from 3.46 to 3.95. This is attributed to Y segregation at the alloy grain boundaries (GBs) and Y-rich phase precipitation, which retards the GB curvature-driven grain growth thermodynamically by a solute drag effect and kinetically by second-phase pinning effect, respectively. Moreover, the Y-free alloy grains grow much faster in air than in Ar, because the surface oxidation in air generates additional tensile stresses in the alloy which facilitate the GB mobility. The Y-containing alloy nanograins remain similar in size during heating in air and in Ar, plausibly due to the formation of more Y-rich oxide particles which hinder the GB mobility through the Zener pinning effect.

Constitutive Model and Cellular Automaton Simulation of the Dynamic Recrystallization of Railway EA4T‐Grade Steel

Herein, isothermal compression experiments are conducted on EA4T steel at 970–1170 °C, with strain rates of 0.01–1.0 s−1 and a strain of 0.2–0.8 s−1. Based on the experimental data, a high‐temperature constitutive model is developed for EA4T steel. The activation energy of dynamic recrystallization (DRX) is calculated to be 383 666 J mol−1, and the correlation coefficient and root mean square error between the results of the constitutive model and experimental results are 0.9943 and 4.6823, respectively. The average grain size for each deformation condition is determined using the linear‐intercept method. The grain growth model widely used in cellular automaton (CA) simulations is found unsuitable for EA4T steel. Therefore, a modified CA model of DRX behavior suitable for EA4T steel is developed. The nucleation rates and solute drag effect coefficients under different deformation conditions are determined. Furthermore, simulations are performed under other deformation conditions using the CA model. The simulated results for the average grain size, microstructure morphology, and DRX fraction agree well with the experimental results. The reason for the deviation between the observed and simulated DRX fractions is also explored.

Effect of Sn4+–Isovalent doping concentration on giant dielectric properties of Sn Ta0.025Ti0.975-O2 ceramics

The Sn x Ta 0.025 Ti 0.975- x O 2 ( x %Sn(TTO)) ceramics with x = 2.5–10% were prepared using a standard mixed-oxide method and sintered at 1450 °C for 3 h to achieve a dense microstructure. The effects of the isovalent–Sn 4+ doping concentration on the crystal structure, microstructure, giant dielectric behavior, and electrical properties were systematically investigated. Continuously enlarged lattice parameters and bond lengths with a single rutile–TiO 2 phase were observed as x % increased. The mean grain size was slightly reduced (∼17.3–14.6 μm) due to an increased oxygen vacancy and the solute drag effect. The dielectric permittivity (ε′) decreased with increasing x %, whereas the loss tangent (tanδ) was remarkably reduced. The semiconducting grain resistance of the x %Sn(TTO) ceramics remained unchanged owing to the same Ta 5+ donor concentration. The insulating grain boundary (GB) resistance was extremely increased by more than two orders of magnitude when x % increased from 2.5 to 5.0%, leading to the significantly improved giant dielectric properties. The optimized low tanδ∼0.02 and high ε′∼10 4 with temperature coefficient less than ±15% in the range of -60–210 °C were reasonably described by the internal barrier layer capacitor model. Improved dielectric properties can be obtained by engineering GB by varying the Sn 4+ –isovalent doping concentration. This study provides an important approach for improving the dielectric properties of co–doped TiO 2 without the creation of complex defect clusters inside the grains.

Comprehensive study on the origin of orthorhombic phase stabilization in Gd-doped HfO2 and DFT calculations.

In recent times, ultra-thin films of hafnium oxide (HfO2) have shown ferroelectricity (FE) attributed to the orthorhombic (o) phase of HfO2 with space group Pca21. This polar o-phase could be stabilized in the doped thin film of the oxide. In the present work, both polar and non-polar o-phases of HfO2 could be stabilized in Gd-doped bulk polycrystalline HfO2. Rietveld analysis of XRD data shows that the relative population of o-phases in the presence of the monoclinic (m) phase of HfO2 increases with increasing Gd-content. The local environment around the host atom has been investigated by time differential perturbed angular correlation (TDPAC) spectroscopy, synchrotron based X-ray near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) measurements. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) measurements showed a reduction in grain size with increasing Gd-dopant indicating a solute drag effect. It could be established that the segregation of the Gd-dopant in the grain boundary is a thermodynamically favorable process and the solute drag effect plays an important role in nucleation of the o-phase in bulk HfO2. Stabilization of Gd in both Pbca and Pca21 phases of HfO2 was supported by defect formation energy calculations using density functional theory (DFT). The present study has important implications in future applications of HfO2 in ferroelectric devices and in understanding the role of dopants in stabilizing the o-phase of HfO2 in the bulk.

Kinetics of static recrystallization in Sn-added Fe-Si alloys

Segregated solute atoms play an important role in grain boundary migration phenomena, which are critical for understanding the microstructure evolution in metals. Recrystallization kinetics of Fe-Si-Sn alloys were experimentally studied during static recrystallization. An established physical model that couples recovery and recrystallization was implemented to describe the experimental observations. The model was extended to include microstructural input, while taking into account the solute drag effect. The model is able to predict both the evolution of the recrystallized fraction and hardness after annealing in the temperature range [773K;1023K] for binary (Fe-5.8at. %Si) and ternary (Fe-5.8at. %Si-0.045at. % Sn) alloys.

Microstructure and dielectric properties of CaCu3Ti4O12-xCeO2 ceramics

(1-x)CaCu3Ti4O12-xCeO2 (x=0.1, 0.2, 0.3, 0.4) and CaCu3Ti4O12 ceramics were synthesized through a solid-state reaction technique. X-ray diffraction indicates that the CaCu3Ti4O12 phase is formed in all ceramics. SEM micrographs show that the grain size of ceramics declines with the addition of CeO2, which is attributed to the solute drag effect. When the addition amount of CeO2 is 0.4, the ceramic obtains the maximum dielectric constant at low frequency. Increasing the composite content of CeO2 can effectively reduce the dielectric loss of CCTO ceramics at high frequency. And the lowest value is 0.1 when the addition amount of CeO2 is 0.3. Impedance analysis shows that the lowest dielectric loss obtained for the ceramic is due to the lowest grain resistance.

Thermal stability, grain growth kinetics, mechanical properties, and bio-corrosion resistance of pure Mg, ZK30, and ZEK300 alloys: A comparative study

Thermal stability, grain growth kinetics, tensile properties, and corrosion resistance of commercially pure (CP) magnesium can be tailored by zinc addition in conjunction with small additions of zirconium and rare earth (RE) elements, which need to be systematically investigated. Accordingly, the thermal stability, grain growth kinetics, tensile properties, and bio-corrosion resistance of hot rolled CP Mg, and ZK30 (Mg-3Zn-0.5Zr) and ZEK300 (Mg-3Zn-0.5RE-0.5Zr) alloys were compared in this work. The solute drag effect of Zn in the ZK30 alloy and the Zener pinning effect of CeZn 5 compound in the ZEK300 alloy were responsible for the improved thermal stability and higher grain growth activation energy of these alloys compared to CP Mg. The tensile properties of hot rolled ZK30 and ZEK300 alloys were superior due to their fine grain sizes. Moreover, corrosion tests in simulated body fluid (SBF) solution confirmed the higher corrosion resistance of the ZEK300 alloy for biomedical implant applications. The shear punch testing (SPT) results revealed that the ZEK300 alloy can better retain its superior mechanical properties during deformation/testing at elevated temperatures. Grain growth annealing led to a decrement in strength but an increment in the total elongations, and hence, the highest tensile toughness was obtained for the ZEK300 alloy with an average grain size of ~ 8.5 μm. Accordingly, this work proposed that RE addition at the micro-alloying level to a lean Mg-Zn alloy is quite effective in the enhancement of thermal stability, room/elevated-temperature mechanical properties, and bio-corrosion resistance.

Influence of alloying element segregation at grain boundary on the microstructure and mechanical properties of Mg-Zn alloy

The role of alloying element segregation at grain boundary on the microstructure and mechanical properties is investigated in the case of Ca, Ce, and Nd addition in Mg-1Zn (wt.%) alloy. Segregation of alloying elements at grain boundary is demonstrated in all the designed ternary alloys, leading to a strong solute drag effect on the mobility of grain boundaries and ultimately the grain size. While the co-segregation of Zn and Ce is revealed in the Mg-Zn-Ce alloy, only the segregation of Zn is observed in the Mg-Zn-Ca alloy. The co-segregation of Zn and Nd in Mg-Zn-Nd alloy is demonstrated to lead to the relatively large solute drag pressure at grain boundary, which in combination with the Zener pressure emerging from nanoscale (Mg, Zn)3Nd precipitates significantly refines the grain size. The grain refinement in combination with the bimodal microstructure significantly contributes to the increased strength of the designed ternary alloys. Furthermore, the addition of Ca and Ce are found to simultaneously improve the strength and ductility, which is closely correlated with the segregation of alloying elements at the grain boundary. Among the considered alloying species, Ce is shown to efficiently improve the mechanical properties of Mg-Zn alloy.

Microstructure, dislocation density and microhardness of 1 %C-doped CoCrFeNi complex concentrated alloys during isochronal annealing

In this study, a microstructure of moderately deformed 1 %C-doped CoCrFeNi complex concentrated alloys (CCA) was investigated in a correlation with microstructure evolution at different annealing temperature for 1 h. After 60 % thickness reduction of cold rolling, the dislocation density accumulated as large as 19 × 1015 m−2. The interstitial carbon atom was a key factor inducing large dislocation storage and caused large stored strain energy of 368 J/mol. The recrystallization was completed at 1173 K for 1 h and the average recrystallized grain size was as fine as 3.7 µm. During the annealing between 973 and 1173 K, the carbides were increasingly precipitated with an increase in annealing temperature. The carbon addition delayed the recrystallization process due to solute drag effect and carbide precipitations. The conventional fabrication method produced the fine recrystallized microstructure attributed to the large dislocation density of the deformed microstructure and carbide precipitation.

An analytical model of grain growth considering the conjoint effects of precipitate pinning and solute drag in steel

ABSTRACT An analytical model is developed to explain the kinetics of grain growth in steel that takes into account all feasible prime phenomena; namely, surface energy reduction, precipitate pinning effect and solute drag effect. The shapes of matrix grains and the precipitates are assumed to be tetrakeidecahedron and spherical, respectively. A single solute and a single type of precipitate are further assumed to be responsible for the solute drag and the precipitate pinning, respectively. An explanation of drag energy is provided in terms of Gibbs free energy change for solute segregation that eventually merges to the well-known Langmuir–McLean relationship. The developed model is validated in view of the existing database in available literature. A new methodology of grain growth analysis is accordingly proposed on the basis of the conceptualised ‘effective migration coefficient’ of the system.

Enhancing mechanical properties of Mg-Gd-Y-Zn alloys via microalloying with Ce and La

This study investigated the microstructure and mechanical properties of Mg-1Gd-1Y-1Zn (at.%) alloys containing designed amounts of Ce or La. The Mg<sub>5</sub>(Gd,Zn) phase formed in the as-cast Mg-Gd-Y-Zn-Ce/La alloys and disappeared after a homogenization treatment at 500°C for 24 h. The addition of Ce and La resulted in the formation of Ce(Mg,Zn)<sub>12</sub> and La(Mg,Zn)<sub>12</sub> phases, respectively. Except for that, the Ce or La addition had no significant effect on the morphology, volume fraction, and type of the long-period stacking ordered (LPSO) phases in the Mg-Gd-Y-Zn alloy. The grain size decreased with increasing microalloying content because the heavy Ce and La atoms impeded atomic migration across the boundaries. The solute drag effect led to the formation of the rare earth texture in the extruded Mg-Gd-Y-Zn-Ce/La alloys, whose extent decreased with increasing microalloying content. The mechanical strength was improved by the addition of Ce or La at the sacrifice of ductility. In particular, La exhibited a stronger reinforcement ability than Ce when it was added to the Mg-Gd-Y-Zn alloys. Among the investigated chemical compositions, the Mg-1Gd-1Y-1Zn-0.3La alloy exhibited the highest strength because it had the finest grains, the highest volume fraction of the second phase, and the weakest texture intensity. Furthermore, the alloys showed an unusual yield asymmetry due to the difference in the deformation mode of the LPSO phase.

Enhanced Toughness of High‐Temperature Carburizing Gear Steel via Refining Twin Martensite and Retained Austenite by Nb Microalloying

High‐temperature carburizing technology is replacing traditional carburizing technology due to energy savings and emission reductions. However, further effort is required to understand the mechanical properties for practical high‐temperature carburizing. Herein, the microstructures and mechanical properties of the 20MnCr5 gear steel with different Nb contents after carburizing at the temperature from 900 to 950 °C and the corresponding holding time from 8 to 5 h are investigated. For a given steel, the toughness slightly decreases with the carburizing temperature because of the increase of prior austenite grain size. For high‐temperature carburizing, the impact energy increases from 45.9 to 84 J after Nb microalloying. The toughening mechanism is analyzed through theoretical discussion and various characterizations of fracture morphology and microstructure. It is indicated that the refinement of prior austenite grain caused by the solute drag effect of Nb leads to the refinement of acicular martensite and retained austenite. The combined effect of microstructure refinement results in the significant enhancement of impact toughness and accompanies by coordinated plastic deformation. The fracture spreads along the martensite blocks due to the decrease in the thickness of twin lamellas in acicular martensite, which also contributes to the enhancement of toughness.

Grain Growth in High-Entropy Alloys (HEAs): A Review

Grain growth is an unavoidable phenomenon occurring during processing of multicomponent high-entropy alloys (HEAs) and medium-entropy alloys (MEAs), which significantly affects the properties and performance of these compositionally complex alloys during service. Accordingly, the present overview article is dedicated to summarize the state of the art of the grain coarsening behavior and its kinetics for HEAs and propose opportunities and scope for future research, with special attention to the Cantor-based compositions. Firstly, the primary recrystallization and grain growth of equiatomic and non-equiatomic CrMnFeCoNi alloys with face-centered cubic (FCC) crystal structure in the single-phase regime and with the presence of intermetallics such as the Cr-rich sigma (σ) phase is considered, which was accompanied by the powerful utilization of the solute drag effect, Zener pinning, and grain boundary segregation engineering via introducing carbon, nitrogen, boron, titanium, and niobium. Subsequently, the quaternary and ternary alloys based on Cr, Mn, Fe, Ni, and Co are taken into account. In these systems, the novel concept of grain boundary high-entropy effect (via the addition of molybdenum, niobium, and zirconium), the formation of pinning insoluble oxide and thermally stable carbide particles during mechanical alloying, the simultaneous solute drag and Zener pinning effects via Mo and C addition, and the formation of Cu-rich phase and the strong segregation effect of Cu atoms to grain boundaries in the FeCoNiCu HEA are critically discussed. Afterward, the thermal stability of AlxFeCoCrNi(Mn) HEAs is treated, where the formation of the Ni–Al-rich B2 phase and the corresponding Zener pinning effect, the influence of aluminum addition on the temperature range for the stability of the σ phase, and cluster drag mechanism of Al atoms are explained. What is more, the grain growth of refractory HEAs with body-centered cubic (BCC) crystal structure is also summarized, where the high grain growth activation energy is attributed to the presence of elements with very low self-diffusivity such as tantalum and niobium. Moreover, the possible effects of short-range ordering on the mobility of grain boundaries are discussed. Finally, the prospects for future research work are presented, including the development of precipitation-temperature-time (PTT) diagrams, systematic investigation of cold rolling and annealing for prior grain refinement, studying abnormal grain growth (secondary recrystallization), and assessment of grain growth behavior of HEAs manufactured by advanced methods such as additive manufacturing (3D printing).

Microstructure and texture evolution during grain growth of AM30 magnesium alloy

ABSTRACT AM30 magnesium alloy was subjected to annealing at temperatures ranging from 200 to 450°C for 1–1440 min to evaluate the microstructure and texture evolution during grain growth. The grain growth exponent of n = 9 and activation energy of Q = 105.6 KJ/mol were observed. Precipitates, such as Mg17Al12, Al8Mn5 and Al11Mn4 were observed in the alloy, and they were found to be reduced with increasing the annealing temperature/time. The precipitates further appeared to be dissolved at a higher annealing temperature of 450°C, leading to abnormal grain growth in the alloy. The effects of solute drag and dislocation density on the grain growth behaviour, estimated through a mesoscale model based on cellular automata, were found to be insignificant during annealing. The strong basal texture in the starting material was observed to be weakened up to 480 mins of annealing, and on further increasing the annealing time to 1440 min, the alloy regained its basal texture. It was found that both normal and abnormal grain growth promoted basal texture during the annealing of the alloy.

Dynamic substrate reactions during room temperature heavy ion irradiation of CoCrCuFeNi high entropy alloy thin films

High entropy alloys (HEAs) are promising materials for various applications including nuclear reactor environments. Thus, understanding their behavior under irradiation and exposure to different environments is important. Here, two sets of near-equiatomic CoCrCuFeNi thin films grown on either SiO2/Si or Si substrates were irradiated at room temperature with 11.5 MeV Au ions, providing similar behavior to exposure to inert versus corrosion environments. The film grown on SiO2 had relatively minimal change up to peak damage levels above 500 dpa, while the film grown on Si began intermixing at the substrate–film interface at peak doses of 0.1 dpa before transforming into a multi-silicide film at higher doses, all at room temperature with minimal thermal diffusion. The primary mechanism is radiation-enhanced diffusion via the inverse Kirkendall and solute drag effects. The results highlight how composition and environmental exposure affect the stability of HEAs under radiation and give insights into controlling these behaviors.

Effect of grain boundary segregation on microstructure and mechanical properties of ultra-fine grained Mg–Al–Ca–Mn alloy wires

An extraordinary high-strength dilute Mg-0.8Al-0.1Ca-0.6Mn (wt. %) alloy wire was successfully developed by hot drawing, which exhibits high tensile yield strength of 394 MPa, ultimate tensile strength of 431 MPa and moderate elongation to failure of 6.0%. The high strength was mainly attributed to the ultra-fine dynamically recrystallized (DRXed) grains, coarse elongated unrecrystallized grains with dense dislocations as well as nano-sized Al2Ca and Al–Mn precipitates dispersed in the as-drawn alloy wire. The microstructure observation by transmission electron microscopy reveals that Al and Ca remarkably co-segregated to the DRXed grain boundaries while Al rather than Ca segregated at the low-angle grain boundaries in the unrecrystallized grains. The solute segregations not only exerted strong solute drag effect on the grain boundaries to restrict the dynamic recrystallization and DRXed grain growth, but also contributed to the high strength of the alloy wire by pinning the dislocations. The findings from this work provide a new insight into the development of strong low-cost and light-weight Mg alloy wires.