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Mg-based alloys 2024

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Please wait a minute... For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails Select Preparation of ultra-high ductility and high strength Mg-Sn-Zn-Zr alloy by differential thermal ECAP (DT-ECAP) induced heterogeneous structure Tianshui Zhou, Bing Wang, Yaqin Li, Shiwen Hu, Xiaoqiang Li, Dexue Liu J. Mater. Sci. Technol.    2024, 199: 222-245.   DOI: 10.1016/j.jmst.2024.01.095 Abstract （36）      PDF       Knowledge map    Developing high-ductility magnesium (Mg) alloys has become an imminent issue for their wide application. In this work, a new Mg-Sn-Zn-Zr alloy with ultra-high ductility (elongation, El. over 40 %) and high ultimate tensile strength (UTS, ～309-354 MPa) was prepared by a novel differential thermal equal-channel angular pressing (DT-ECAP). Heterogeneous structures, including bimodal grain structures and inhomogeneous distribution of second phases composed of banded structure and particle free zone (PFZ), were induced by DT-ECAP process. Based on the results of electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and selected area electron diffraction (SAED), the bimodal grain structure originated from incomplete dynamic recrystallization (DRX) dominated by Zener pinning, strain-induced grain boundary migration (SIBM) and the limitation of polycrystallization due to lower dislocation density. Meanwhile, the bimodal distribution of second phases was highly associated with the defect density and initial structure. More importantly, the enhanced strength of DT-ECAPed alloys can be primarily attributed to hetero-deformation induced (HDI) strengthening, grain boundary strengthening, and precipitation strengthening. Moreover, HDI hardening, texture weakening or randomizing activation of non-basal slip, high density of dislocations in sub-structures, and twining induced superior work-hardening effect, which was highly responsible for the ultra-high ductility in sixth pass (6P) alloy. The current work provides a novel DT-ECAP process for inducing heterogeneous structure and offers beneficial insight into the development of ultra-high ductility and high strength for rare-earth-free Mg alloys via a combination of HDI strengthening and hardening and other vital mechanisms. Reference | Related Articles | Metrics Select Track-Rex: A universal toolbox for tracking recrystallization nucleation and grain growth behaviors in polycrystalline materials Xun Zeng, Haoran Yi, Zhuoran Zeng, Liang Yuan, Sangbong Yi, Junheng Gao, Mark Rainforth, Dikai Guan J. Mater. Sci. Technol.    2024, 197: 149-159.   DOI: 10.1016/j.jmst.2024.02.013 Abstract （28）      PDF       Knowledge map    Recrystallization annealing is widely used to tailor the microstructure and enhance the performance of cold-deformed metallic materials. However, the underlying recrystallization mechanisms are debated, even with the use of cutting-edge characterization techniques. Here, we develop a Track-Rex toolbox to analyze quasi-in-situ electron backscatter diffraction (EBSD) datasets of two magnesium (Mg) alloys during static recrystallization via grain correlation. The results show that the recrystallized grains do not always grow; instead, they can shrink or even be consumed. This is attributed to the presence of newly formed recrystallized grains that possess a growth advantage over the old recrystallized grains. The rare earth containing Mg-2.4Zn-0.2Ce wt.% (ZE20) alloy exhibits a higher nucleation activity in the shear bands compared to the commercial Mg-3Al-1 Zn (AZ31) alloy. Regardless of the nucleation timing and sites, recrystallized grains in the ZE20 alloy show consistent off-basal orientations, serving as the origin of the rare earth texture. Moreover, the off-basal texture of these recrystallized grains is further strengthened through preferential growth during subsequent annealing. On the contrary, the recrystallized grains in the AZ31 exhibit scattered basal orientations that grow uniformly, resulting in a weak basal texture. Reference | Related Articles | Metrics Select Development of a superb degradable lightweight Mg alloy with high compressive strength Zhang Liu, Shao-Chuan Zheng, Bo-Yu Liu, Ming Liu, Dong-Lang Chai, Zhi-Wei Shan J. Mater. Sci. Technol.    2024, 194: 180-184.   DOI: 10.1016/j.jmst.2023.12.073 Abstract （51）      PDF       Knowledge map    Lightweight Mg alloys with high degradation rates and high strength are attractive for fracturing tools used in unconventional oil/gas extraction. The common design strategy for such alloys is to directly add Ni/Cu into existing high-strength Mg alloys, which meets the high-strength demand but the degradation rates are still insufficient for some extreme downhole environments, especially those with low temperature and low chloride ion concentrations. Here we designed an extruded lightweight Mg-Li-Ni-Cu alloy with superb degradation rate and high strength. The high degradation rate is attributed mainly to the formation of highly effective galvanic couples, Ni/Cu-containing second phases (cathode) and Mg-Li matrix (anode) with ultrahigh potential difference. The degradation rate achieved 2404.3 mm/y, ～2.3 times higher than the reported highest rate of extruded Mg alloys for fracturing tools. The alloy also has a high compressive strength of 484.9 MPa, which can be attributed largely to grain refinement strengthening. Reference | Related Articles | Metrics Select Anticorrosion and discharge performance of calcium and neodymium co-doped AZ61 alloy anodes for Mg-air batteries Baosheng Liu, Ang Gao, Zhechao Zhang, Muhun He, Ben Bin Xu, Xuetao Shi, Pengpeng Wu, Sijie Guo, Mohammed A. Amin, Eman Ramadan Elsharkawy, Zhanhu Guo J. Mater. Sci. Technol.    2024, 193: 132-145.   DOI: 10.1016/j.jmst.2024.01.024 Abstract （34）      PDF       Knowledge map    Calcium (Ca) and neodymium (Nd) were introduced in the AZ61 alloy as alloying elements. The microstructure, corrosion behavior, and discharge properties of AZ61-1Nd-xCa (x = 0, 0.5 wt.%, 1 wt.%, 2 wt.%) alloys as anodes for Mg-air batteries were systematically investigated. The results indicated that the AZ61-1Nd-1Ca alloy exhibits the best corrosion resistance during electrochemical experiments and hydrogen evolution tests. Discharge performance tests showed that the AZ61-1Nd-1Ca alloy exhibits the best specific capacity (1193.6 mAh g-1), energy density (1893.7 mWh g-1), anode efficiency (60.3 %), and cell voltage (1.246 V) at higher current densities. This is mainly attributed to the addition of Ca element, which refines the grain size of the alloy and increases the grain boundary area. In addition, Al2Nd and Al2Ca phases have similar corrosion mechanisms in the cross-section of the extruded alloy. The precipitated granular Al2Ca phase is uniformly dispersed on the substrate and acts as a physical barrier. This not only enhances the corrosion resistance of the alloy but also improves the anode efficiency of the alloy during discharge. Reference | Related Articles | Metrics Select Effects of Mg17 Al12 phase on microstructure evolution and ductility in the AZ91 magnesium alloy during the continuous rheo-squeeze casting-extrusion process Dijia Zhao, Shulin Lü, Wenbo Guo, Shilong Li, Jianyu Li, Guanghui Guo, Wei Guo, Shusen Wu J. Mater. Sci. Technol.    2024, 191: 63-79.   DOI: 10.1016/j.jmst.2023.12.031 Abstract （45）      PDF       Knowledge map    In this study, a high-ductility AZ91 magnesium alloy was fabricated by the novel continuous rheo-squeeze casting-extrusion (CRSCE) process. The semi-solid slurry was prepared by ultrasonic vibration (UV) treat-ment, then solidified under pressure, and finally hot extruded. UV treatment can reduce the Al element content in primary grains and increase it in secondary grains. The refined Mg17 Al12 phase was scattered along secondary grain boundaries and then stretched into narrow, fibrous bands during the hot extrusion. The fibrous bands with proper separation distances can accelerate the dynamic recrystallization (DRX) process and suppress the growth of DRXed grains. Microcracks were initiated inside the brittle Mg17 Al12 phase and tended to propagate along the continuously distributed Mg17 Al12 phase during the tensile test. Thus, the tiny Mg17 Al12 phase in the billet and narrow, fibrous bands in as-extruded rods can prevent cracks from spreading and enhance ductility. Therefore, excellent comprehensive mechanical properties were obtained, with an ultimate tensile strength of 326.3 MPa and an elongation of 16.46 %. The CRSCE method offers a novel way to fabricate high-ductility and high-alloyed magnesium alloys without ho-mogenization. Microstructure regulation mechanisms of CRSCE, microstructural hereditary laws, and the effect of the Mg17 Al12 phase on mechanical properties were further discussed. Reference | Related Articles | Metrics Select Recrystallization behavior and microstructure evolution of Mg-5Bi-3Al alloy during very high-speed extrusion Sang-Cheol Jin, Ye Jin Kim, Dong Hee Lee, Sang-Ho Han, Sumi Jo, Sung Hyuk Park J. Mater. Sci. Technol.    2024, 191: 233-249.   DOI: 10.1016/j.jmst.2023.11.074 Abstract （34）      PDF       Knowledge map    In our previous study, we extruded Mg-5Bi-3Al (BA53, wt.%) alloy at a very high speed of 70 m/min, and the high-speed-extruded alloy exhibited an unusual fine grain structure. Since dynamic recrystal-lization (DRX) behavior determines the microstructure and corresponding mechanical properties of the extruded alloy, understanding its origin is crucial for further improvement and optimization of alloys. Herein, the DRX behavior during high-speed extrusion of the recently developed BA53 alloy was inves-tigated in detail by analyzing the microstructure and texture of the extrusion butt along the extrusion path obtained by water quenching the remaining part of the billet immediately after extrusion. During the initial stages of extrusion with a high extrusion speed of 70 m/min and a high temperature of 400 ℃, tension twinning predominantly occurred in grains with a high Schmid factor (SF), switching the c -axis of the grains toward the transverse direction of the butt and causing the formation of a ring basal texture. In the intermediate stage, the microstructural changes were dominated by continuous and discontinuous DRX, resulting in the formation of fine recrystallized grains and orientation distribution originated from the parent grain. DRX was completed in the late stage wherein unrecrystallized grains with low SF for basal slip contributed to the late-stage recrystallization, strengthening the ring basal texture. Addition-ally, DRXed grains with favorable orientation for basal slip underwent lattice rotation, contributing to the formation of the obvious ring basal texture. Finally, preferential grain growth occurred after the DRX, leading to an increase in texture intensity and grain size of the extruded alloy. Therefore, the fine grain structure and ring basal texture obtained through high-speed extrusion were primarily attributed to the activated discontinuous DRX facilitated by a high strain rate and temperature. Reference | Related Articles | Metrics Select Metal-organic framework [NH2-MIL-53(Al)] functionalized TiO2 nanotube photoanodes for highly stable and efficient photoelectrochemical cathodic protection of nickel-coated Mg alloy Huan Yao, Ruifeng Zhang, Yu Wen, Yue Liu, Gang Yu, Zhi-Hui Xie J. Mater. Sci. Technol.    2024, 182: 67-78.   DOI: 10.1016/j.jmst.2023.09.038 Abstract （48）      PDF       Knowledge map    Metal-organic framework [MOF, i.e., NH2-MIL-53(Al)] modified TiO2 (NMT) composite photoanodes were successfully prepared by hydrothermal synthesis and were used for the photoelectrochemical cathodic protection (PECCP) of nickel-plated magnesium alloy (Mg/Ni). Results showed that the synthesis temperature significantly impacted the morphology and PECCP performance of the NMT photoanodes. The NMT@150 photoanode prepared at a reaction temperature of 150 °C exhibited the best PECCP performance and produced a current density of 1980 μA cm-2 under visible light irradiation, which was 19.8 times higher than that of a single TiO2 photoanode. The composite photoanode could polarize the open circuit potential of the coupled Mg/Ni electrode to -876 mV and remain relatively stable within 35 h. XPS and EPR tests showed that a Z-scheme heterojunction was formed between the NH2-MIL-53(Al) and TiO2 nanotubes, allowing the photogenerated electrons to accumulate mainly on the conduction band of NH2-MIL-53(Al). The heterojunction greatly promoted the separation and transfer of photogenerated electron-hole in the NMT composite photoanode, significantly enhancing the PECCP performance for Mg/Ni. Reference | Related Articles | Metrics Select Additive manufacturing of porous magnesium alloys for biodegradable orthopedic implants: Process, design, and modification Bo Peng, Haojing Xu, Fei Song, Peng Wen, Yun Tian, Yufeng Zheng J. Mater. Sci. Technol.    2024, 182: 79-110.   DOI: 10.1016/j.jmst.2023.08.072 Abstract （94）      PDF       Knowledge map    Biodegradable magnesium (Mg) alloys exhibit excellent biocompatibility, adequate mechanical properties, and osteogenic effect. They can contribute to complete recovery of damaged tissues without concerns about a second surgery and have achieved clinical applications in orthopedic and cardiovascular fields. Porous scaffolds can provide functions such as bone integration and adjustable mechanical properties, thus widely used for bone repair. Additive manufacturing (AM) offers the advantages of design freedom and high precision, enabling the reliable production of porous scaffolds with customized structures. The combination of biodegradable Mg alloys, porous scaffolds, and AM processes has created tremendous opportunities for the precision treatment of bone defects. This article reviews the current development in the additive manufacturing process and design of Mg alloy biodegradable orthopedic implants, focusing on chemical compositions, structural design, surface treatment, and their effects on mechanical properties, degradation behavior, and biocompatibility. Finally, the future perspective of porous Mg alloy biodegradable orthopedic implants is proposed. Reference | Related Articles | Metrics Select Relationship between solidification path, microstructure evolution and solidification cracking behavior of Mg-Al-Ca alloy during TIG welding Sensen Chai, Qingwei Dai, Shiyu Zhong, Qingshan Yang, Limeng Yin, Dingfei Zhang, Jingkai Feng, Qian Li J. Mater. Sci. Technol.    2024, 182: 176-186.   DOI: 10.1016/j.jmst.2023.10.016 Abstract （47）      PDF       Knowledge map    The high-strength and creep-resistant Mg-Al-Ca-Mn alloys have broad application prospects. However, solidification cracking occurs in these alloys in certain conditions and the origin is still unclear. This work investigated the relationship between the solidification path, microstructure evolution and solidification cracking behavior of the Mg-xAl-2Ca-Mn alloys during tungsten inert gas (TIG) welding. Results show that when the fusion zone's Ca/Al mass ratio ranges from 0.4 to 1.64, solidification cracking occurs at a Ca/Al mass ratio of ～0.7. As the Ca/Al mass ratio approaches this value, the grain size increases, and the Laves phases are reduced gradually. The early formed Laves phases play an important role in promoting dendrite segmentation, refining grain size and enhancing grain boundaries. When a solidification path delays the formation of Laves phases, the Laves phases will be reduced accompanied by grain coarsening. In such a solidifying microstructure, intergranular cavitation is easy to occur, and the resistance of the semi-solid alloy to crack propagation is severely reduced. Reference | Related Articles | Metrics Select Influence of high temperature oxidation on mechanical properties and in vitro biocompatibility of WE43 magnesium alloy fabricated by laser powder b e d fusion Jinge Liu, Shuyuan Min, Zijun Mao, Mengran Zhou, Bingchuan Liu, Dazhi Liu, Fei Song, Peng Wen, Yun Tian, Yufeng Zheng J. Mater. Sci. Technol.    2024, 179: 26-39.   DOI: 10.1016/j.jmst.2023.08.056 Abstract （54）      PDF       Knowledge map    Laser powder bed fusion (L-PBF) has been used to fabricate biodegradable Mg implants of WE43 alloy, but the degradation is too fast compared with the term bone reconstruction. Previous studies show that high temperature oxidation (HTO) can successfully inhibit the degradation of WE43 alloy. In this work, the in?uence of HTO on L-PBF samples of WE43 alloy was investigated regarding tensile, compressive, and abrasive resistance, as well as in vitro cytotoxicity, cell proliferation, hemolysis, and osteogenesis. Compared with the as-built L-PBF samples, HTO increased grain size and grain texture, stabilized and coarsened precipitates, and caused discontinuous static recrystallization in the matrix. The oxide layer at the surface of the HTO samples improved surface roughness, hydrophilia, hardness, and abrasive resis-tance. The tensile strength decreased slightly from 292 to 265 MPa, while the elongation substantially increased from 10.97% to 16.58% after HTO. The in vitro cell viability, cell proliferation, hemolysis, and osteogenic effect were considerably enhanced due to the improvement of surface quality and the initial inhibition of excessive Mg2+ releasement. Overall, HTO is of great bene?t to the surface performance, ductility, and biocompatibility of WE43 alloy fabricated by L-PBF for biodegradable applications. Reference | Related Articles | Metrics Select Optimization of the in vitro biodegradability, cytocompatibility, and wear resistance of the AZ31B alloy by micro-arc oxidation coatings doped with zinc phosphate Chao Yang, Suihan Cui, Ricky K.Y. Fu, Liyuan Sheng, Min Wen, Daokui Xu, Ying Zhao, Yufeng Zheng, Paul K. Chu, Zhongzhen Wu J. Mater. Sci. Technol.    2024, 179: 224-239.   DOI: 10.1016/j.jmst.2023.09.019 Abstract （1613）      PDF       Knowledge map    As implanted bone fixation materials, magnesium (Mg) alloys have significant advantages because the density and elastic modulus are closest to those of the human bone and they can bio-degrade in the physiological environment. However, Mg alloys degrade too rapidly and uncontrollably thus hampering clinical adoption. In this study, a highly corrosion-resistant zinc-phosphate-doped micro-arc oxidation (MAO) coating is prepared on the AZ31B alloy, and the degradation process is assessed in vitro. With increasing zinc phosphate concentrations, both the corrosion potentials and charge transfer resistance of the AZ31B alloy coated with MAO coatings increase gradually, while the corrosion current densities diminish gradually. Immersion tests in the simulated body fluid (SBF) reveal that the increased zinc phosphate concentration in MAO coating decreases the degradation rate, consequently reducing the release rates of Mg2+ and OH- in the physiological micro-environment, which obtains the lowest weight loss of only 5.22% after immersion for 56 days. Effective regulation of degradation provides a weak alkaline environment that is suitable for long-term cell growth and subsequent promotion of bone proliferation, differentiation, mineralization, and cytocompatibility. In addition, the zinc-phosphate-doped MAO coatings show an improved wear resistance as manifested by a wear rate of only 3.81?×?10-5 mm3 N-1 m-1. The results reveal a suitable strategy to improve the properties of biodegradable Mg alloys to balance tissue healing with mechanical degradation. Reference | Related Articles | Metrics Select Hot extrusion-induced Mg-Ni-Y alloy with enhanced hydrogen storage kinetics Xuan Sun, Xiaohua Yang, Yangfan Lu, Qun Luo, Chengzhang Wu, Yu Zhang, Tao Lyu, Qinfen Gu, Qian Li, Fusheng Pan J. Mater. Sci. Technol.    2024, 202: 119-128.   DOI: 10.1016/j.jmst.2024.03.009 Abstract （36）      PDF       Knowledge map    In this work, the influence of the hot-extrusion method on the hydrogen storage kinetics of Mg-Ni-Y alloy was investigated. It was shown that the extruded Mg91.47Ni6.97Y1.56 alloy exhibits improved hydriding and dehydriding (H/D) kinetics, with a capacity of 3.5 wt.% H2 absorption within 60 s and 5.4 wt.% H2 desorption within 5 min at 573 K. The dehydrogenation activation energy of extruded alloy is 71.4 kJ mol-1, smaller than that of as-cast alloy (140.5 kJ mol-1). The enhancement of H/D kinetics is attributed to the microstructural refinement and increased grain/phase boundaries introduced by hot extrusion, as well as the catalytic effects from the in-situ generated and grain-refined Mg2Ni and YH2 particles during the H/D process. Furthermore, the dehydrogenated rate-determining step transforms from hydrogen diffusion in the hydride (as-cast alloy) to the surface penetration of hydrogen atoms (extruded alloy). These findings provide crucial insights for the design of Mg-based hydrogen storage alloys in the future. Reference | Related Articles | Metrics Select Micromechanics in Mg alloys: Role of hard Al2RE precipitates Hui Su, Junsheng Wang, Chengpeng Xue, Guangyuan Tian, Shuo Wang, Xinghai Yang, Quan Li, Yisheng Miao, Zhihao Yang, Yanan Meng J. Mater. Sci. Technol.    2024, 200: 112-128.   DOI: 10.1016/j.jmst.2024.02.041 Abstract （36）      PDF       Knowledge map    The influence of hard Al2RE phases (Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) on the overall and local deformation as well as damage mechanism of Mg alloys has been studied by using a crystal plasticity model based on dislocation density with a brittle damage criterion. Microcracks that lead to swift damage initiation and propagation throughout the matrix have been predicted. It has been found that the hard Al2RE with higher elastic modulus enhances the damage resistance of the Mg matrix, which was confirmed by fracture SEM/EDS characterizations and phase-field damage simulation. This discovery provides valuable insights for designing Mg alloys with both high stiffness and enhanced damage resistance. Reference | Related Articles | Metrics Select Atomic-scale investigation of precipitate phases in QE22 Mg alloy Xiaojun Zhao, Zhiqiao Li, Aiping Zhang, Longlong Hao, Houwen Chen, Jian-Feng Nie J. Mater. Sci. Technol.    2024, 177: 114-127.   DOI: 10.1016/j.jmst.2023.07.070 Abstract （36）      PDF       Knowledge map    Precipitation-hardenable commercial Mg alloy QE22 (Mg-2.5Ag-2.0Nd-0.7Zr, wt.%) has excellent mechanical properties, but precipitates in this alloy have not been well understood. In this work, precipitate phases γ'', γ, and δ formed during the isothermal ageing process at 150, 200, 250, and 300 °C have been characterized using atomic-resolution high-angle annular dark-field scanning transmission electron microscopy and atomic-scale energy-dispersive X-ray spectroscopy. The morphology, crystal structure, and orientation relationship of these precipitate phases have been determined. Domain boundaries usually exist in a single γ particle, which can be characterized by a separation vector of [11¯01]α. The δ phase forms in situ from its precursor γ phase, consequently leading to the formation of three different variants within a single δ particle. The nucleation of the δ phase is strongly related to the domain boundaries of the γ phase. The formation of the γ phase may be promoted by its precursor γ'' phase. The similarities in atomic structures of the γ'', γ, and δ phases are described and discussed, indicating that transformations between these precipitate phases can be accomplished through the diffusion of added alloying elements. Reference | Related Articles | Metrics Select Unexpected effects on creep resistance of an extruded Mg-Bi alloy by Zn and Ca co-addition: Experimental studies and first-principles calculations Zhenyu Xiao, Shiwei Xu, Weiying Huang, Haifeng Liu, Xuyue Yang, Haikun Xu, Chao Ma, Chen Jin, Zhanhong Lin J. Mater. Sci. Technol.    2024, 201: 166-186.   DOI: 10.1016/j.jmst.2024.01.083 Abstract （29）      PDF       Knowledge map    In the present work, a new Mg-Bi based alloy is developed by the addition of Zn and Ca in equivalent atom fraction with Bi. Mg-Bi and Mg-Bi-Zn-Ca alloys were prepared by extrusion at a ram speed of 20 mm/s. Room temperature mechanical properties and creep behaviors at 423 K were investigated. The results show that Zn and Ca co-addition shows little influence on average grain size and texture intensity but changes the dispersive Mg3Bi2 into Mg2Bi2Ca particles in different sizes and a lower density. Twinning is largely activated during room-temperature deformation. Consequently, a slightly decreased proof strength but tripled elongation is shown at room temperature. Unexpectedly, large enhancement in creep resistance is detected after the co-alloying of Zn and Ca and the minimum creep rate is reduced by 10 to 20 times in the BZX621 alloy. Stress exponent n = 4-5 indicates that the creep is a dislocation-climb controlled type. Post-mortem characterization on microstructure shows slip of dislocation 〈c + a〉 are also largely found in B6 as well as BZX621 alloy and cross-slip is detected more severe in B6 alloy. Dynamic segregation and precipitation are also seen in both alloys. Bi-clusters are seen dispersive across the grains in B6 and so did the PFZs that could undermine creep resistance at the grain boundaries. By contrast, Zn-rich needle-like precipitates are developed at most “ends” of 〈c + a〉 dislocations, which would hinder the further dislocation motions and thus improve the creep resistance. First-principles calculations were adopted and the results show that the thermal stability and thermomechanical properties of Mg2Bi2Ca are much better than that of Mg3Bi2. Stacking faults energy is lowered down with the co-addition of Ca and Zn, which could inhibit the rate of dislocation climb and cross-slip. As a result, the improved creep resistance is obtained in the Mg-Bi-Zn-Ca alloys. Microstructural and controlling mechanism changes by thermal activation result in the unexpected enhancement in creep resistance with decreased room-temperature proof strength after co-addition. These findings could contribute to the development and optimization of creep-resistant Mg alloys in the future. Reference | Related Articles | Metrics Select Refining 18R-LPSO phase into sub-micron range by pre-kinking design and its prominent strengthening effect on Mg97Y2Zn1 alloy Chao Sun, Huan Liu, Ziyue Xu, Yuna Wu, Kai Yan, Jia Ju, Jinghua Jiang, Feng Xue, Jing Bai, Yunchang Xin J. Mater. Sci. Technol.    2024, 176: 13-24.   DOI: 10.1016/j.jmst.2023.07.051 Abstract （51）      PDF       Knowledge map    In this study, a composite deformation strategy of pre-kinking (equal channel angular pressing (ECAP)) followed by large-ratio hot extrusion (HE) was designed to refine the 18R long period stacking ordered (LPSO) phase into sub-micron range in a Mg97Y2Zn1 (at.%) alloy. After the composite processing, the mechanical properties of the alloy are significantly enhanced, superior to the majority of reported Mg97Y2Zn1 and other LPSO-containing Mg alloys. Among the composite deformed alloys, the 16P-HE alloy exhibits the best mechanical properties with tensile yield strength (TYS) of 475 MPa, ultimate tensile strength (UTS) of 526 MPa, and fracture elongation (FE) of 14.5%. Quantitative analysis of 18R phase indicates that increasing ECAP pass from 1 to 16 gradually decreases the average size of 18R phase from 5.1 µm to 2.3 µm. After HE, the 18R phase is further refined with a corresponding decrease in the average size in the descending order of 1P-HE (4.3 µm), 4P-HE (3.2 µm), and 16P-HE (1.4 µm) alloys. Calculation of the strengthening contributions confirms that the superior mechanical properties of 16P-HE alloy are mainly due to its strongest interface strengthening (145 MPa) and grain boundary strengthening (189 MPa) from the sub-micron 18R phase and α-Mg grains. Moreover, the strengthening effect of 18R phase decreases gradually with their morphology changing from particles to fibers, and to blocks. The obtained results further deepen and broaden the strengthening-toughening theory of 18R phase. Reference | Related Articles | Metrics Select Portland cementitious coating with autogenerated oxide film and its anticorrosion behavior on magnesium alloy Danqian Wang, Ye Wang, Kai Ma, Chaoneng Dai, Jinxing Wang, Jingfeng Wang, Fusheng Pan J. Mater. Sci. Technol.    2024, 176: 99-111.   DOI: 10.1016/j.jmst.2023.04.079 Abstract （45）      PDF       Knowledge map    A simple one-step anticorrosion Portland cement (PC)-based coating with an autogenerated oxide film on the surface of Mg alloy was successfully prepared in this study. The anticorrosion of coated Mg alloys was assessed by several electrochemical methods including open circuit potential, electrochemical impedance spectroscopy, and cyclic potentiodynamic polarization. The morphology and composition of PC-based coatings were characterized via scanning electron microscopy and X-ray diffraction. The composition of the autogenerated oxide film was analyzed via X-ray photoelectron spectroscopy. Results show that the PC-based coatings can significantly enhance the corrosion resistance of AZ41 Mg alloy due to the synergetic effect of PC-based coating and autogenerated oxide film. Particularly, the quality of oxide film plays a dominant role in determining anticorrosion of Mg alloy. Furthermore, the addition of metakaolin and dolomite enhances the resistance of PC-based coating and meanwhile, MoO42- ions from PC-based coating can adsorb in the oxide film, improving the quality of the oxide film. Reference | Related Articles | Metrics Select Effect of cross rolling on the microstructure and mechanical performance of a dual-phase structured Mg-8Li-6Zn-1Y (in wt.%) alloy Dongliang Wang, Daokui Xu, Baojie Wang, Changjian Yan, Shuo Wang, Xiangbo Xu, Lan Zhang, Cuilan Lu J. Mater. Sci. Technol.    2024, 176: 132-144.   DOI: 10.1016/j.jmst.2023.07.052 Abstract （48）      PDF       Knowledge map    The microstructure and mechanical performance of the unidirectionally and cross-directionally rolled Mg-8Li-6Zn-1Y (in wt.%) sheets have been investigated and compared. It reveals that after the unidirectional rolling (UR), the broken I-phase particles are aggregated at the α-Mg/β-Li phase interfaces. However, the cross-rolling (CR) process can not only severely break the bulk I-phase, but also cause the obviously uniform distribution of I-phase particles in the matrix phases. Moreover, the average grain size of the CR samples is 3.61 μm and about 50% that of the UR samples. The maximum texture intensities of α-Mg and β-Li phases in the CR samples are slightly stronger than those in the UR samples. Tensile results demonstrate that the CR process can effectively enhance the tensile properties and remarkably reduce the mechanical anisotropy of the alloy. For the UR samples, the yield strength, ultimate tensile strength, and elongation ratio along the rolling direction (RD) are 164 MPa, 198 MPa, and 16.4%, whereas those along the transverse direction (TD) are 157 MPa, 185 MPa, and 22.0%, respectively. For the CR samples, their mechanical properties are basically the same and the mechanical anisotropy is almost eliminated. The yield strength, ultimate tensile strength, and elongation ratio along the cross-rolling direction 1 (CRD1) and 2 (CRD2) are respectively measured to be 181 MPa and 182 MPa, 220 MPa and 218 MPa, 20.6% and 20.7%. Failure analysis indicates that for the UR samples being tensile tested along the RD and TD, micro-cracks are preferentially initiated in the region of aggregated I-phase particles. For the CR samples being tensile tested along both two cross-rolling directions, the initiation of micro-cracks mainly occurs at the I-phase/matrix phase interfaces and in the interior of matrix phases. Reference | Related Articles | Metrics Select Unveiling strength-plasticity synergic mechanism of AZ91 alloy during multi-DOF forming Fang Chai, Xinghui Han, Zhiyuan Ma, Lin Hua, Xuan Hu, Wuhao Zhuang, Fangyan Zheng J. Mater. Sci. Technol.    2024, 195: 80-92.   DOI: 10.1016/j.jmst.2024.02.004 Abstract （33）      PDF       Knowledge map    High performance is of great importance to expand the application of magnesium alloys, and the inherent strength-plasticity synergic mechanism during a specific process should be unveiled. In this paper, a multi-degrees of freedom (multi-DOF) forming process is conducted on initially extruded AZ91 magnesium alloy at different deformation degrees, including small deformation with deformation amounts of 10% and 20%, medium deformation with deformation amounts of 30% and 40%, and large deformation with deformation amounts of 60% and 70%. Simultaneous enhancement of ultimate tensile strength (UTS) and plasticity is achieved in all these multi-DOF processed alloys in comparison to the initially extruded one. As deformation degrees increase, both UTS and elongation of the multi-DOF processed alloy gradually increase in small and medium deformation and then slightly decrease in large deformation, exhibiting a superior strength (401 MPa) and plasticity (16.3%) combination at deformation amount of 40%. The evolution of mechanical properties varying with deformation degrees is closely dependent on microstructure and texture characterization. The microstructures of multi-DOF processed AZ91 alloy are increasingly refined and heterogeneous as deformation degrees gradually increase, which consist of the predominant equiaxed coarse grains (CGs) and a few fine grains (FGs) in small deformation, some CGs (equiaxed or slightly elongated) and some FGs in medium deformation, and some remarkably elongated CGs and the predominant FGs in large deformation. The area fraction of basal texture gradually decreases while that of prismatic texture gradually increases with increasing deformation degrees, finally resulting in a complete disappearance of basal texture at a deformation amount of 70%. Thus, the strength-plasticity synergic mechanism related to increasingly obvious heterogeneous structure, gradually refined microstructure, and gradually decreased basal texture contribute to the constantly simultaneous improvement of UTS and plasticity until in medium deformation, and the remarkably elongated CGs play a significant role in the slight decrease of UTS and plasticity in large deformation even with further increasing grain refinement and decreasing basal texture. This research provides an efficient and novel way to achieve strength-plasticity synergic magnesium alloy via optimizing microstructure and texture. Reference | Related Articles | Metrics Select Development of magnesium alloys: Advanced characterization using synchrotron radiation techniques Enyu Guo, Zelong Du, Xiaobo Chen, Zongning Chen, Huijun Kang, Zhiqiang Cao, Yiping Lu, Tongmin Wang J. Mater. Sci. Technol.    2024, 195: 93-110.   DOI: 10.1016/j.jmst.2024.01.029 Abstract （38）      PDF       Knowledge map    Magnesium alloys are the lightest metal structural materials owing to their excellent physical and chemical properties. Microstructural evolution in magnesium alloys under the conditions of casting, thermal-mechanical processing, and in-service environment, play an important role in governing their mechanical properties and reliability/sustainability. A synchrotron light source produces high flux, tunable X-ray energy, high resolution, and high coherence X-ray beams, which can realize in-situ dynamic observation of microstructural evolution in a wide range of alloys during the entire processing chain and in simulated service environments. This article reviews the fundamentals of synchrotron radiation characterization techniques (imaging, diffraction, scattering, and fluorescence holography) and state-of-the-art advanced synchrotron characterization techniques on the microstructure evolution mechanism of magnesium alloys. Case studies span a broad range of solidification, deformation, precipitation, fracture and damage, corrosion, and energy storage. Research opportunities and challenges of physical metallurgy studies of magnesium alloys are highlighted for future studies. Reference | Related Articles | Metrics Select Microscopic and mesoscopic deformation behaviors of dual-phase Mg-Li-Gd alloys Jing Li, Li Jin, Fulin Wang, Chuhao Liu, Huamiao Wang, Jie Dong J. Mater. Sci. Technol.    2024, 194: 1-15.   DOI: 10.1016/j.jmst.2023.12.064 Abstract （88）      PDF       Knowledge map    The Mg-Li dual-phase alloys, comprised of hexagonal (HCP) and body-centered cubic (BCC) phases, exhibit a better combination of strength and ductility than Mg single-phase alloys. In this work, the deformation behaviors of Mg-6Li-2Gd and Mg-2Gd alloys, representatives of dual-phase and single-phase alloys, have been studied at both microscale and mesoscale to elucidate the underlying mechanisms. Nanoindentation results show that the α-Mg phase in the Mg-6Li-2Gd alloy is harder than the β-Li phase. The intergranular deformation incompatibility, which arises from the elastic-plastic interactions, different strain accommodation behaviors, and strain hardening behaviors between the hard α-Mg phase and the soft β-Li phase, leads to pronounced hetero-deformation induced (HDI) stress of the Mg-6Li-2Gd alloy. The HDI stress strengthens the two phases simultaneously, so that the yield strength of the dual-phase Mg-6Li-2Gd alloy is higher than the Mg-2Gd alloy as well as the harder α-Mg phase in the Mg-6Li-2Gd alloy. Due to the decreased strength difference between the two phases caused by the HDI stress strengthening, the dual-phase alloy exhibits homogeneous plasticity at the mesoscale, which benefits the elongation of the Mg-6Li-2Gd alloy. The HDI strengthening magnitude in the Mg-6Li-2Gd alloy is further quantified. Based on the equal strain upper bound and equal stress lower bound approximations, the yield strength improved by the HDI stress is estimated to be 18-37 MPa, which is in the same range as the elastic visco-plastic self-consistent (EVPSC) simulation results. As the tensile strain is larger than ～3 %, the HDI strengthening magnitude for the Mg-6Li-2Gd alloy reaches 50-65 MPa, accounting for 35 % of the corresponding flow stress. Reference | Related Articles | Metrics Select Achieving exceptional strength and ductility combination in a heterostructured Mg-Y alloy with densely refined twins Yuliang Yang, Yuxin Liu, Shuang Jiang, Ye Yuan, Weiye Chen, Lifang Sun, Zhufeng He, Xiaoli Zhao, Nan Jia J. Mater. Sci. Technol.    2024, 189: 132-145.   DOI: 10.1016/j.jmst.2023.11.042 Abstract （76）      PDF       Knowledge map    Metals and alloys with heterogeneous microstructures are an emerging class of materials that exhibit exceptional mechanical properties, owing to the novel scientific principle of hetero-deformation induced (HDI) strengthening and hardening. For magnesium alloys, due to their low recrystallization temperature, poor ductility at room temperature, limited cold workability, and the tendency to generate strong basal texture during deformation, it is difficult to obtain heterostructures without relying on precipitation of the second phases. Here, three heterostructured Mg-2.9Y (wt.%) materials with varying accumulative equivalent true strains, i.e., 5 %-5 cycles, 7.5 %-5 cycles, and 10 %-5 cycles materials were fabricated via applying five complete triaxial compression cycles to the bulk alloy. The 5 %-5 cycles material with an accumulative equivalent true strain of 0.37 is featured with long twin lamellae embedded in coarse grains. When the accumulative true strain increases to 0.72, a heterogeneous structure composed of long and short twin lamellae is formed inside the 7.5 %-5 cycles material. As the equivalent true strain further increases to 1.01, the 10 %-5 cycles material exhibits a mixed structure with densely refined twin lamellae embedded in the coarse-grained matrix. The room-temperature uniaxial tensile tests show that the yield strength of the materials processed by triaxial cyclic compression (TCC) has been significantly improved compared to that at the initial state, whereas ductility was not significantly sacrificed without the subsequent heat treatment. The dense and refined twin lamellae that serve as hard domains in this material provide a high density of interfaces and impede dislocation motion effectively. This results in significant HDI strengthening and hardening. These findings provide new insight into the design of heterostructured hexagonal close-packed materials with both high strength and good ductility. Reference | Related Articles | Metrics Select Gradient microstructure and superior strength-ductility synergy of AZ61 magnesium alloy bars processed by radial forging with different deformation temperatures Jingfeng Zou, Lifeng Ma, Yanchun Zhu, Ling Qin, Yuan Yuan J. Mater. Sci. Technol.    2024, 170: 65-77.   DOI: 10.1016/j.jmst.2023.07.003 Abstract （42）      PDF       Knowledge map    Gradient microstructure modification is a cost-efficient strategy for high strength without compromising ductility, which is urgently needed in the fundamental science of engineering materials. In this study, heterogeneous structures of AZ61 alloy bars with anisotropic gradients (with different grain size distributions from the surface to the center) were observed to exhibit strong strength-ductility synergies under different deformation temperatures. The results reveal that the grain refinement process under medium-low temperature deformation conditions (≤ 350 °C) consists of four transition stages along the radial direction, i.e., twin activations and deformation band formations, dislocation cells and pile-ups, ultrafine sub-grains, and randomly orientated quasi-micron grains. Different deformation temperatures have a great influence on twin activations and deformation band formations, and the high temperature can easily provoke the initiation of non-basal slip. The deformation bands were determined as a primary nucleation site due to their highly unstable dislocation hindrance ability. Analysis in combination with the Radial forging (RF) deformation process, the differences of dynamic precipitates can be attributed to microstructural difference and solubility limit of Al at different temperatures. By summarizing the tensile test results, the sample forged at 350 °C exhibited the best strength-ductility synergy, exhibiting the highest elongation (EL) of 23.2% with a 251 MPa yield strength (YS) and 394 MPa ultimate tensile strength (UTS) in center region, and combined with the highest strength value of 256 MPa YS and 420 MPa UTS in the center region, while the EL was slightly degraded to 19.8%. Reference | Related Articles | Metrics Select Effect of initial grain size on the recrystallization behavior and recrystallization texture of a Mg-3Gd alloy Fang Han, Xuan Luo, Knut Marthinsen, Guilin Wu, Ziyong Hou, Xiaoxu Huang J. Mater. Sci. Technol.    2024, 188: 169-182.   DOI: 10.1016/j.jmst.2023.11.044 Abstract （38）      PDF       Knowledge map    The effect of initial grain size on the recrystallization and recrystallization texture of a rolled Mg-3Gd (wt.%) alloy is studied in detail. The results show that the deformation microstructure of an initially coarse-grained (CG) sample has a larger twinned area and a higher density of twin boundaries than a fine-grained (FG) sample. After annealing, the CG sample recrystallizes preferentially in the twinned area, whereas the FG sample adopts the higher density grain boundaries as the nucleation sites. Furthermore, weak recrystallization texture components appear from the grain nucleation stage, regardless of the initial grain size, and are preserved after complete recrystallization due to uniform grain growth. The majority of recrystallization texture is deviated 20°-45° away from normal direction (ND), accounting for more than 50 %. Especially, the recrystallization texture of the FG sample is a “Rare Earth texture”, in contrast to the widely reported texture modification unrelated to grain boundary nucleation. Only a scattered basal texture is observed in the CG sample, which also differs from the reported “Rare Earth texture” originating from shear band nucleation in dilute Mg-Gd alloys. Finally, based on the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model, the recrystallization kinetics are calculated, and it is found that the initial grain size mainly affects the nucleation rate, and has limited effect on the grain growth rate. Reference | Related Articles | Metrics Select Achieving exceptionally high strength and rapid degradation rate of Mg-Er-Ni alloy by strengthening with lamellar γ′ and bulk LPSO phases Chaoneng Dai, Jingfeng Wang, Yuanlang Pan, Kai Ma, Yinhong Peng, Ye Wang, Danqian Wang, Chunhua Ran, Jinxing Wang, Yanlong Ma J. Mater. Sci. Technol.    2023, 168: 88-102.   DOI: 10.1016/j.jmst.2023.02.064 Abstract （54）      PDF       Knowledge map    As-extruded Mg-Er-Ni alloys with different volume fractions of long-period stacking ordered (LPSO) phase and density of lamellar γ′ phase were prepared, and the microstructure, mechanical, and degradation properties were investigated. Coupling the bulk LPSO phase and the lamellar γ′ phase, and controlling the dynamic recrystallization processes during deformation by adjusting the volume fraction of LPSO and the density of the γ′ phase, a synergistic increase in strength and degradation rate can be achieved. On the one hand, the increase in corrosion rate was related to the increased volume fraction of the bulk LPSO phase and the densities of the lamellar γ′ phase, which provide more galvanic corrosion. Moreover, high densities of the lamellar γ′ phase can provide more corrosion interface by inhibiting the recrystallization process to refine dynamic recrystallized (DRXed) grains during the hot extrusion. On the other hand, the ultimate tensile strength (UTS) and tensile yield strength (TYS) of the Mg-Er-Ni alloy increased from 345 and 265 MPa to 514 MPa and 358 MPa, respectively, which was mainly attributed to grain boundary and texture strengthening, bulk LPSO phase and lamellar γ′ phase strengthening. Overall, Mg-14Er-4Ni alloy, which contains the highest volume fraction bulk LPSO phase and the densities of lamellar γ′ phase, realized a synergistic enhancement of strength and degradation rate. The UTS, TYS, and degradation rate of Mg-14Er-4Ni were 514 MPa, 358 MPa, and 142.5 mg cm-2 h-1 (3 wt% KCl solution at 93 ℃), respectively. This research provides new insight into developing Mg alloys with high strength and degradation rates for fracturing tool materials in the application of oil and gas exploitation in harsh environments. Reference | Related Articles | Metrics Select Improvement of the conversion efficiency of Mg3Sb2 thermoelectric devices through optimizing the resistivity of the MgSbNi barrier layer Huimin Zhang, Yachao Wang, Zuhair A. Munir, Yongzhong Zhang, Wenhao Fan, Shaoping Chen J. Mater. Sci. Technol.    2023, 168: 208-214.   DOI: 10.1016/j.jmst.2023.05.034 Abstract （36）      PDF       Knowledge map    Mg3Sb2-based thermoelectric materials have been the focus of widespread investigations as promising candidates for the harvesting of waste heat. Interface stability and service performance are key points for the commercial applications of these materials. We utilized Mg4.3Sb3Ni as a barrier layer to improve the thermal stability of Mg3Sb2-based devices. However, its intrinsic high resistivity contributed negatively to the desired performance of the device. In this work, we investigated two other Mg-Sb-Ni ternary phases, MgSbNi and MgSbNi2, as new barrier layer materials to connect with Mg3.2Sb2Y0.05. The results show that the efficiency of the Mg1.2SbNi/Mg3.2Sb2Y0.05/Mg1.2SbNi joint is increased by 33% relative to the higher Mg-content barriers due to lower resistivity. The system exhibited good interfacial compatibility and showed little change with aging at 673 K for 20 days. Reference | Related Articles | Metrics Select Significantly improve the strength and ductility of AZ31 Mg alloy by introducing pure Ti Xiang Chen, Dabiao Xia, Qixiang Jia, Guangsheng Huang, Weizhang Wang, Junlei Zhang, Heung Nam Han, Fusheng Pan J. Mater. Sci. Technol.    2024, 185: 69-82.   DOI: 10.1016/j.jmst.2023.11.008 Abstract （47）      PDF       Knowledge map    In this work, we introduced pure Ti into AZ31 Mg alloy by extrusion process followed by annealing at 350 °C for 1 h to significantly improve the mechanical properties of AZ31 laminate, with a yield strength of 243 MPa, an ultimate tensile strength of 338 MPa and a uniform elongation of 17.7%. Microstructural characterizations showed that there was slight diffusion of elements (Al, Zn, and Mn) across the layer interface, and the interface between the constituent layers maintained semi-coherent. Moreover, significant microstructure heterogeneities appeared across the hetero-interface, where the Mg layer possessed large equiaxed grains with lower dislocation density, while the Ti layer formed ultrafine grains (UFG) and unrecrystallized block grains with extensive dislocation cells and dislocation walls. Combining the digital image correlation (DIC) technique and in-situ electron backscatter diffraction (EBSD), it was found that the microstructural heterogeneities induced significant strain gradients near the layer interface during plastic deformation, which needed to be accommodated by geometrically necessary dislocations (GNDs). This resulted in hetero-deformation-induced (HDI) strengthening and HDI strain hardening to strengthen and toughen the AZ31 laminated composite. Additionally, the introduction of the Ti layer effectively hindered the propagation of the cracks and consequently improved the ductility of the laminate. Reference | Related Articles | Metrics Select Microstructural evolution and its influence on mechanical and corrosion behaviors in a high-Al/Zn containing duplex Mg-Li alloy after friction stir processing Yixing Zhu, Mengran Zhou, Yingxin Geng, Shun Zhang, Tongzheng Xin, Gaoqiang Chen, Yifan Zhou, Xiaoyu Zhou, Ruizhi Wu, Qingyu Shi J. Mater. Sci. Technol.    2024, 184: 245-255.   DOI: 10.1016/j.jmst.2023.10.019 Abstract （41）      PDF       Knowledge map    Ultralight Mg-Li alloys offer promising applications across various fields. Mg-Li alloys enriched with Al and Zn hold theoretical potential for achieving excellent mechanical strength and corrosion resistance. However, the structural and performance characteristics of such Mg-Li alloys, particularly after thermomechanical processing, remain inadequately explored and understood. This study investigated the microstructural evolution of a Mg-9Li-5Al-4Zn alloy after friction stir processing and its consequent effects on the mechanical and corrosion performance. The grain size of the alloy was effectively refined and stabilized during friction stir processing at various heat inputs. The yield strength of the alloy increased by 86.4% after friction stir processing under the highest heat input condition, which was attributed to fine grain strengthening, solid solution strengthening and dispersion strengthening. Concurrently, the alloy experienced a slight decrease in elongation after the friction stir processing. The alloy subjected to friction stir processing with the highest heat input exhibited a minimal corrosion current density of 6.10 × 10-6 A/cm2, which was only 25% of the base metal. The enhanced anti-corrosion properties can be attributed to the dispersion and distribution of precipitated particles induced by friction stir processing, which hindered the micro-galvanic corrosion and promoted the generation of a compact surface film, leading to minimal and uniform corrosion. This investigation can be significant for understanding the metallurgical mechanisms and performance evolution of Mg-Li alloys during thermomechanical processes. Reference | Related Articles | Metrics Select Balanced strength and ductility by asymmetric gradient nanostructure in AZ91 Mg alloy Bingqian Xu, Jiapeng Sun, Lingling Wang, Jing Han, Guosong Wu J. Mater. Sci. Technol.    2024, 184: 167-179.   DOI: 10.1016/j.jmst.2023.10.027 Abstract （38）      PDF       Knowledge map    High-strength Mg alloys have historically suffered from a challenge in achieving good ductility. Here, we report an asymmetric gradient nanostructure design prepared by ultrasonic severe surface rolling (USSR) at room temperature. Unlike conventional gradient-nanostructured materials that employ a hard-soft-hard sandwich structure, this new design incorporates a combined gradient distribution of grain microstructure and nanoprecipitates throughout the entire sample along the thickness direction. The nanoprecipitates are identified as the β-Mg17Al12 phase and are primarily generated through In-situ precipitation promoted by the USSR-induced high-density dislocations and temperature increment. Benefiting from this unique microstructure, an outstanding strength-ductility synergy is achieved, with a yield strength of 372.8 MPa, an ultimate tensile strength of 453.3 MPa, and an elongation of 11.5%. The enhanced strength can be attributed to several mechanisms, including grain boundary strengthening, dislocation strengthening, precipitation strengthening, twin strengthening, and hetero-deformation induced (HDI) strengthening. The HDI hardening and activation of multiple deformation modes also contribute to good ductility. This work provides a promising and effective method for overcoming the longstanding strength-ductility trade-off dilemma in Mg alloys. Reference | Related Articles | Metrics Select Texture adjustment approach of magnesium alloys via variable strain path calculated by an integrated finite element-viscoplastic self-consistent model Wenjie Wu, Wenzhen Chen, Xiaoyu Wang, Wenke Wang, Wencong Zhang, Xinhua Liu, Hyoung Seop Kim J. Mater. Sci. Technol.    2024, 184: 15-31.   DOI: 10.1016/j.jmst.2023.09.054 Abstract （42）      PDF       Knowledge map    An integrated calculated approach based on weakly coupled finite element (FEM)-viscoplastic self-consistent (VPSC) model was established to simulate the texture evolution during the variable strain path extrusion process of magnesium alloys. The spiral die extrusion (SDE) process with additional circumferential shear deformation was applied to investigate the effect of path control on texture adjustment and verify the accuracy of the model. The results indicated that the additional spiral shear resulting from the overall inclined flow path effectively reduced the intensity of the {0002}//ED fiber texture by suppressing basal slip activation in the core area, while the local shear deformation along the spiral equal channel strain path led to the formation of an inclined {0002}//ND plane texture on the side. Using the modified Hall-Petch relationship, the correlation between texture and yield strength was quantified. Specifically, the weakening of the texture effectively suppressed {10-12} tensile twinning, which compensated for the deficiency of compressive yield strength without significantly sacrificing tensile yield strength, and thus improved the tension-compression asymmetry. Furthermore, the strongly inclined {0002}//ND plane texture inhibited the widespread activation of basal slip during tensile yielding, thereby enhancing the yield strength. Reference | Related Articles | Metrics

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