Journal of Magnesium and Alloys最新文献

{"title":"Additive manufacturing high-strength and ultra-high-rare-earth magnesium alloys: Excellent long-time aging hardening and strengthening behavior","authors":"Zhe Xu ,&nbsp;Zhuo Li ,&nbsp;Chunjie Shen ,&nbsp;Dongdong Zheng ,&nbsp;Yuxuan Tu","doi":"10.1016/j.jma.2025.04.007","DOIUrl":"10.1016/j.jma.2025.04.007","url":null,"abstract":"<div><div>Gadolinium (Gd) is one of the most effective strengthening elements for magnesium alloys. The development of commercially available Mg-Gd alloys with high Gd content and the optimization of their preparation processes have been a major focus in magnesium alloy research. In this study, a Mg-23Gd-2Zn-0.4Zr alloy with ultra-high Gd content is designed, and high-quality fabrication is achieved using laser-directed energy deposition (LDED) technology. Through heat treatment and microstructure control, a balance between tensile strength (425 MPa) and elongation (3.4%) is achieved. The ultra-high strength of the LDED-T6 VZ232K alloy is primarily attributed to precipitation strengthening caused by the ultra-high density (2.4 × 10⁴ µm^-2) of β′ phase. The high ductility is mainly due to the modification of the fracture mode, facilitated by the introduction of a substantial number of stacking fault structures during solution heat treatment. The extended hardness plateau (exceeding 138 Hv) and high yield strength (exceeding 300 MPa) are associated with the three-directional cross-interlocked structure of the β′ phase in the over-aged state at 220 °C and 250 °C. The analysis of the LDED-VZ232K alloy indicates that reduced heat input during the additive manufacturing (AM) process is critical for the defect-free fabrication of alloys with ultra-high Gd content.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3829-3846"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143932515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Developing a novel high-strength Mg-Gd-Y-Zn-Mn alloy for laser powder bed fusion additive manufacturing process","authors":"Qingchen Deng,&nbsp;Zhiyu Chang,&nbsp;Ning Su,&nbsp;Jing Luo,&nbsp;Yaoyuan Liang,&nbsp;Yuhao Jin,&nbsp;Yujuan Wu,&nbsp;Liming Peng,&nbsp;Wenjiang Ding","doi":"10.1016/j.jma.2023.09.027","DOIUrl":"10.1016/j.jma.2023.09.027","url":null,"abstract":"<div><div>Laser powder bed fusion (LPBF) of Mg alloys mainly focuses on the traditional commercial casting Mg alloys such as AZ91D, ZK60 and WE43, which usually display relatively low tensile strengths. Herein we developed a novel high-strength Mg-12Gd-2Y-1Zn-0.5Mn (wt.%, GWZ1221M) alloy for the LPBF additive manufacturing process, and the evolution of microstructure and mechanical properties from the as-built state to LPBF-T4 and LPBF-T6 states was systematically investigated. The as-built GWZ1221M alloy exhibited fine equiaxed grains with an average grain size of only 4.3 ± 2.2 µm, while the as-cast alloy displayed typical coarse dendrite grains (178.2 ± 73.6 µm). Thus, the as-built alloy showed significantly higher tensile strengths than the as-cast counterpart, and its yield strength (YS), ultimate tensile strength (UTS) and elongation (EL) were 315 ± 8 MPa, 340 ± 7 MPa and 2.7 ± 0.5% respectively. Solution treatment transformed hard and brittle β-(Mg,Zn)₃(Gd,Y) phase into basal X phase and lamellar long period stacking ordered (LPSO) with better plastic deformability, leading to the improvement of EL. Then peak-aging heat treatment introduced numerous nano-sized prismatic β′ precipitates inside grains, resulting in the enhancement of YS. Finally, the LPBF-T6 alloy achieved appreciably high strength with YS, UTS and EL of 320 ± 3 MPa, 395 ± 4 MPa and 2.1 ± 0.4% respectively. Both as-built and LPBF-T6 GWZ1221M alloys showed remarkably higher tensile strengths than the as-cast counterparts and as-built commercial Mg alloys, highlighting the great potential of high-strength as-built Mg-Gd based alloys for structural applications.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3713-3724"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71475029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase transitions, lattice dynamics, thermal transport, and thermodynamic properties of Mg2V2O7 from experiments and first-principle calculations","authors":"Guishang Pei ,&nbsp;Xin Jin ,&nbsp;Mengjiao Jiao ,&nbsp;Zhuoyang Li ,&nbsp;Dapeng Zhong ,&nbsp;Junyi Xiang ,&nbsp;Ruixiang Zhu ,&nbsp;Rui Wang ,&nbsp;Yuntao Xin ,&nbsp;Xuewei Lv","doi":"10.1016/j.jma.2023.11.013","DOIUrl":"10.1016/j.jma.2023.11.013","url":null,"abstract":"<div><div>Mg₂V₂O₇ is the most promising candidate for low-temperature co-fired ceramic (LTCC) multilayer devices. Selecting the appropriate precursors strongly requires reliable thermodynamic properties to be defined accurately. In this study, the structural parameters of the Mg₂V₂O₇ at ambient temperature indicate that it is crystallized in space group of <em>P</em>2₁<em>/c</em>. Notably, Mg₂V₂O₇ has low lattice thermal conductivity (<em>k_L</em>) of 4.77, 5.12, and 4.52 W/mK, along the <em>a, b</em>, and <em>c</em> axes, respectively, which originates from the large phonon scattering rate and low phonon group velocity. The α-Mg₂V₂O₇↔β-Mg₂V₂O₇ and β-Mg₂V₂O₇↔γ-Mg₂V₂O₇ polymorphic transitions occur at 743 °C and 908 °C with enthalpy change of 1.82±0.04 kJ/mol and 1.51±0.04 kJ/mol, respectively. The endothermic effect at 1083 °C with an enthalpy change of 26.54±0.26 kJ/mol is related to the congruent melting of γ-Mg₂V₂O₇. In addition, the molar heat capacity of Mg₂V₂O₇ was measured utilizing drop calorimetry at high temperatures. The measured thermodynamic properties were then applied to select precursors for preparing Mg₂V₂O₇ via a solid-state reaction, indicating that the V₂O₅ and Mg(OH)₂ precursors are strongly recommended due to their thermodynamic superiority.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3632-3641"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139550843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Statistical investigation on the tension-compression asymmetry of slip behavior and plastic heterogeneity in an aged Mg-10Y sheet","authors":"Ran Ni ,&nbsp;Huashen Liu ,&nbsp;Shen Hua ,&nbsp;Hao Zhou ,&nbsp;Ying Zeng ,&nbsp;Dongdi Yin","doi":"10.1016/j.jma.2024.11.033","DOIUrl":"10.1016/j.jma.2024.11.033","url":null,"abstract":"<div><div>The grain-scale tension-compression (T-C) asymmetric slip behavior and geometrically necessary dislocation (GND) density in an aged and twin-free Mg-10Y sheet were statistically studied using slip trace analysis and electron backscatter diffraction (EBSD) analysis. A significantly asymmetric slip activity, i.e., higher tensile slip activity and proportion of non-basal slip, was manifested. Prismatic 〈a〉 (37.1%) and basal 〈a〉 (27.6%) slips dominated the tensile deformation, followed by pyramidal II 〈<em>c</em> + <em>a</em>〉 slip (20.0%). While during compression, basal 〈a〉 slip (61.9%) was the most active slip mode, and only 6.9% pyramidal II 〈<em>c</em> + <em>a</em>〉 slip was observed. The critical resolved shear stress (CRSS) ratio was estimated based on ∼800 sets of the identified slip traces, which suggested that the CRSS_{pyr II}/CRSS_bas for compression was ∼3 times than that of tension. The pyramidal II 〈<em>c</em> + <em>a</em>〉 slip was more active when the slip plane was under tension than under compression, which was consistent with the calculated asymmetric CRSS_{pyr II}/CRSS_bas. The activity of multiple slip, cross slip and slip transfer, as well as the GND density were also T-C asymmetric. This work thoughtfully demonstrated the T-C asymmetric slip behavior and plastic heterogeneity in Mg alloys which was believed to be responsible for the macroscopic T-C asymmetry when twinning was absent. The present statistical results are valuable for validating and/or facilitating crystal plasticity simulations.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3880-3895"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142832013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From macro-, through meso- to micro-scale: Densification behavior, deformation response and microstructural evolution of selective laser melted Mg-RE alloy","authors":"Cheng Chang ,&nbsp;Guangrui Yao ,&nbsp;Sophie C. Cox ,&nbsp;Xiaofeng Zhang ,&nbsp;Liyuan Sheng ,&nbsp;Min Liu ,&nbsp;Weili Cheng ,&nbsp;Yang Lu ,&nbsp;Xingchen Yan","doi":"10.1016/j.jma.2024.12.018","DOIUrl":"10.1016/j.jma.2024.12.018","url":null,"abstract":"<div><div>To clarify the densification behavior, deformation response and strengthening mechanisms of selective laser melted (SLM) Mg-RE alloys, this study systematically investigates a representative WE43 alloy via advanced material characterization techniques. A suitable laser output mode fell into the transition mode, allowing for the fabrication of nearly full-density samples (porosity = 0.85 ± 0.021%) with favorable mechanical properties (yield strength=351 MPa, ultimate tensile strength = 417 MPa, the elongation at break = 6.5% and microhardness = 137.9 ± 6.15 HV_0.1) using optimal processing parameters (<em>P</em> = 80 W, <em>v</em> = 250 mm/s and <em>d</em> = 50 µm). Viscoplastic self-consistent analysis and transmission electron microscopy observations reveal that the plastic deformation response of the SLM Mg-RE alloys is primarily driven by basal &lt;<em>a</em>&gt; and prismatic &lt;<em>a</em>&gt; slips. Starting from a random texture before deformation (maximum multiple of ultimate density, Max. MUD = 3.95), plastic stretching led the grains to align with the Z-axis, finally resulting in a {0001}&lt;<span><math><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>0</mn></mrow></math></span>&gt; texture orientation after fracture (Max. MUD = 8.755). Main phases of the SLM state are mainly composed of α-Mg, Mg₂₄Y₅ and β’-Mg₄₁Nd₅, with an average grain size of only 4.27 µm (about a quarter of that in the extruded state), resulting in a favorable strength-toughness ratio. Except for the nano-β’ phase and semi-coherent Mg₂₄Y₅ phase (mismatch = 16.12%) around the grain boundaries, a small amount of nano-ZrO₂ and Y₂O₃ particles also play a role in dispersion strengthening. The high mechanical properties of the SLM state are chiefly attributed to precipitation hardening (44.41%), solid solution strengthening (34.06%) and grain boundary strengthening (21.53%), with precipitation hardening being predominantly driven by dislocation strengthening (67.77%). High-performance SLM Mg-RE alloy components were manufactured and showcased at TCT Asia 2024, receiving favorable attention. This work underscores the significant application potential of SLM Mg-RE alloys and establishes a strong foundation for advancing their use in the biomedical fields.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3947-3963"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strengthening/weakening effect of graphene orientation angle on mechanical properties of AZ91 magnesium matrix composites","authors":"Dunwei Peng ,&nbsp;Zhuo Song ,&nbsp;Yunpeng Zhang ,&nbsp;Xiaopan Wang ,&nbsp;Hua Hou ,&nbsp;Yuhong Zhao","doi":"10.1016/j.jma.2024.12.001","DOIUrl":"10.1016/j.jma.2024.12.001","url":null,"abstract":"<div><div>Graphene, as the reinforcing phase of magnesium matrix composites, can effectively improve the material strength, elastic modulus, and other properties. However, the random distribution of graphene in the matrix (i.e., random orientation angle) leads to different reinforcement effects on the matrix. To gain a deeper understanding of the impact of monolayer graphene (1LG) with varying orientation angles on the properties of Mg-9Al-1Zn (AZ91 (wt.%)) magnesium alloy, molecular dynamics (MD) simulations are employed to analyze the mechanical properties of AZ91/1LG composites under uniaxial tension. The simulation results show that Young's modulus and tensile strength of AZ91/1LG composites decrease gradually with the increase of the orientation angle of the 1LG. The Young's modulus and tensile strength of AZ91/1LG composites can be improved by the 1LG orientation angle of 0°∼10°, where the two are enhanced by 21.7% and 19.7% respectively, at an orientation angle of 0°. However, the Young's modulus and tensile strength of 1LG are decreased for orientation angles of 20°∼90°. Atomic structure evolution analysis revealed that the deformation mechanism of AZ91/1LG nanocomposites mainly depended on the load transfer ability of 1LG with different orientation angles, the bonding ability with AZ91 magnesium alloy matrix and the change of dislocation density. By fitting the formula to the tensile strength of AZ91/1LG composites with different orientation angles of 1LG, it is found that the simulated data of the AZ91/1LG composites containing a 1LG has a maximum relative error of about 10% concerning the fitted empirical formula to calculate the data. The maximum relative error for AZ91/1LG composites containing multiplate 1LG with different orientation angles is 7%. In addition, the interaction between graphene and dislocations in AZ91 magnesium matrix was further explained by transmission electron microscopy (TEM) and phase-field-crystal (PFC) simulation. It can provide some technical guidance for the experimental process design of AZ91/1LG composites.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3659-3672"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142917943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low-energy and accelerated hydrogen release from MgH2–5 wt% NaTiOxH catalyzed hydrogen storage reactor by graphite responsive microwave","authors":"Bofei Wang ,&nbsp;Zhen Wu ,&nbsp;Honghao Liu ,&nbsp;Fusheng Yang ,&nbsp;Zaoxiao Zhang ,&nbsp;Jing Yao ,&nbsp;Qian Li ,&nbsp;Hujun Cao ,&nbsp;Bo Li","doi":"10.1016/j.jma.2025.03.002","DOIUrl":"10.1016/j.jma.2025.03.002","url":null,"abstract":"<div><div>Owing to high thermal stability and large reaction enthalpy, MgH₂ has high reaction temperatures and sluggish reaction kinetics in the dehydrogenation process, which consumes lots of energy. To achieve hydrogen release with low energy consumption, accelerated reaction rate, and high heating uniformity, this paper proposes a novel method of graphite responsive microwave-assisted thermal management with NaTiO<em>_x</em>H catalyst. A multi-physics model of the 5 wt% NaTiO<em>_x</em>H catalyzed MgH₂ reactor integrated with a microwave generator is developed to investigate the reaction, heat and mass transfer process of hydrogen release. It is found that the graphite responsive microwave heating method could improve the temperature uniformity of reaction bed, reduce the energy consumption by at least 10.71% and save the hydrogen release time by 53.49% compared with the traditional electric heating method. Moreover, the hydrogen desorption thermodynamics could be improved with the increase of microwave power. The hydrogen release time is shortened by 19.55% with the increase of 20 W microwave power. Meanwhile, it is also concluded that the microwave excitation frequency of 2.1 GHz and the graphite content of 2 wt% have better heating performance. Therefore, it can be verified that the graphite responsive microwave heating helps to low-energy and accelerated hydrogen release from MgH₂ hydrogen storage reactor.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3864-3879"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure-activity relationship on tensile properties under DRX and slip system activity of U-CVCDEed AZ31 magnesium alloy","authors":"Qiang Liu ,&nbsp;Feng Li ,&nbsp;Fu Wei Kang ,&nbsp;Hai Bo Wang ,&nbsp;Shun Luo","doi":"10.1016/j.jma.2025.03.010","DOIUrl":"10.1016/j.jma.2025.03.010","url":null,"abstract":"<div><div>Given the limitations of traditional hot extrusion methods in improving the microstructure and mechanical properties of magnesium(Mg) alloys, this paper attempts to treat AZ31 Mg alloy billet by pre-upsetting continuous variable cross-section direct extrusion (U-CVCDE). The effects of dynamic recrystallization behavior and slip system activity on texture evolution and mechanical properties of CVCDE Mg alloys with different pre-upsetting amounts were systematically analyzed. The results indicate that the introduction of the pre-upsetting process promotes dynamic recrystallization during the CVCDE process. The recrystallization proportion shows a trend of first rising and then decreasing with the increase of the pre-upsetting amount. Among them, the proportion of recrystallization grains in the U2-CVCDE-formed structural parts is as high as 88.3%. The average grain sizes of U1-CVCDE, U2-CVCDE, and U3-CVCDE were 6.01 µm, 4.90 µm, and 10.45 µm, respectively. In addition, following U-CVCDE, the pyramidal slip of each forming component consistently maintains a high level of activation and opening and dominates, making more grains deflect in the axial extrusion direction of C to varying degrees, which is conducive to the uniform distribution of stress in more grains during plastic deformation. The synergistic effect of dynamic recrystallization behavior and the high activity of the pyramidal slip system significantly weakened the (0001) basal texture strength, and the maximum basal texture strength showed a gradually decreasing trend, among which the base surface texture strength of U3-CVCDE formed parts was only 9.9. The U-CVCDE process is employed to achieve deep modification of Mg alloy, and excellent comprehensive mechanical properties are obtained; among them, the yield and tensile strength of U2-CVCDE are as high as 243.4 MPa and 317.5 MPa, respectively, and the elongation after breaking is up to 21.3%. This study introduces a practical new idea for investigating the extrusion forming technology of high-performance Mg alloys.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3906-3917"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anodic behaviour of Mg at pre-breakdown stages of PEO in basic electrolytes","authors":"Yuchen Lu ,&nbsp;Aleksey Rogov ,&nbsp;Sepideh Aliasghari ,&nbsp;Aleksey Yerokhin","doi":"10.1016/j.jma.2025.06.021","DOIUrl":"10.1016/j.jma.2025.06.021","url":null,"abstract":"<div><div>Electrolyte selection for Plasma Electrolytic Oxidation (PEO) of magnesium is important as this determines composition, morphology and properties of resultant coatings that are urgently sought after for protection of Mg alloys from corrosion and wear in harsh environments. However, electrolyte design is often performed heuristically, which hampers the development and optimisation of new PEO processes. Here, we attempt to achieve a mechanistic understanding of electrochemical and microstructural aspects of anodic films evolution at the pre-breakdown stages of PEO treatments of magnesium in aqueous alkaline solutions of NaAlO₂, Na₃PO₄, NaF and Na₂SiO₃. Systematic studies have shown that magnesium self-passivation by MgO/Mg(OH)₂ can be compromised by both chemical and mechanical instabilities developed due to side effects of anodic reactions. Stable initiation of PEO process requires maintaining surface passivity in a wide range of pH, which can be achieved only by combining self-depositing passivators with those binding dissolved magnesium into insoluble compounds.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3596-3616"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144786562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revealing stir zone heterogeneities in friction stir-welded and annealed AZ31 alloy","authors":"Hiba Azzeddine ,&nbsp;Salaheddine Sadi ,&nbsp;Farazila Yusof ,&nbsp;François Brisset ,&nbsp;Thierry Baudin ,&nbsp;Megumi Kawasaki","doi":"10.1016/j.jma.2025.07.009","DOIUrl":"10.1016/j.jma.2025.07.009","url":null,"abstract":"<div><div>The difference in the microstructure, texture in the stir zone (SZ) of the AZ31 (Mg-3Al-1Zn, wt.%) alloy after friction stir welding (FSW) and subsequent annealing at 400 °C for 1 h was characterized by scanning electron microscopy (SEM) with electron backscatter diffraction (EBSD) measurements at the surface and core regions. The findings indicate that FSW produced grain refinement where the mean grain size decreases from 19 µm (base metal) to 5.1 and 3.5 µm at the surface and core regions, respectively. The c-axis of the grains at the surface region was aligned with the normal direction (&lt;0001&gt;//ND) due to the additional strain of the tool shoulder. In contrast, the core region shows a typical shear texture, where the c-axis tends to be oriented parallel to the welding direction (&lt;0001&gt;//WD). The Vickers microhardness mapping across the SZ revealed that the core region was soften than the surface region due to the dynamic recrystallization and texture weakening. The microstructure of the SZ remains principally deformed after annealing treatment except for the development of massive Mg₁₇Al₁₂ precipitates and the abnormal grain growth of a few grains with &lt;11−20&gt;//WD orientation at the upper side of the surface region. The c-axis of the grains at the surface region was tilted about 10° toward WD, while an inclined &lt;0001&gt;//WD orientation about 30° from WD was developed at the core region. Consequently, the distribution of microhardness values across the SZ was more heterogeneous than the FSW sample. The results were discussed in the light of grain boundary misorientation, dislocation density and the pinning effect of Mg₁₇Al₁₂ precipitates. Additionally, Schmid factor analysis was used to examine the activation of the basal slip mode to characterize the associated mechanical response.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 8","pages":"Pages 3986-4004"},"PeriodicalIF":13.8,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144840168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}