Journal of Magnesium and Alloys最新文献

{"title":"Developing a novel Mg2Zn3Li1Gd alloy sheet with high room-temperature formability by introducing an elliptical texture distribution","authors":"Guangjie Xue ,&nbsp;Junjie He ,&nbsp;Yang Chen ,&nbsp;Zijian Zhang ,&nbsp;Kun Yang ,&nbsp;Yilun Zhou ,&nbsp;Huijun Hao ,&nbsp;Weiqi Wang ,&nbsp;Yong Mao ,&nbsp;Qinghang Wang","doi":"10.1016/j.jma.2024.04.026","DOIUrl":"10.1016/j.jma.2024.04.026","url":null,"abstract":"<div><div>In recent years, modification of texture distribution has been considered a valid approach to improve the room-temperature (RT) formability of magnesium (Mg) alloys. In this study, a novel Mg<img>2Zn<img>3Li<img>1Gd alloy sheet with weak elliptical-texture was fabricated by cold rolling and subsequent annealing, and it showed an excellent Erichsen (IE) value near 7.1 mm. Both quasi-in-situ electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) analysis indicate that considerable basal and pyramidal dislocations can be activated in the cold rolling process. During annealing, these dislocations can induce nucleation and then cause preferential misorientation relationships around 〈uvt0〉 concerning the nuclei and parent grains, which can facilitate the formation of elliptical texture. Furthermore, the particle-stimulated nucleation (PSN) mechanism and the co-segregation of Zn and Gd at grain boundaries (GB) further weak texture intensity. Finally, the mechanical properties of the Mg<img>2Zn<img>3Li<img>1Gd alloy sheet are significantly improved.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 877-893"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141053520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Achieving excellent mechanical properties in Mg-5Bi-3Al alloy via ultra-fine grain and high-density precipitates","authors":"Hongrui Li ,&nbsp;Chong Wang ,&nbsp;Yukang An ,&nbsp;Enyu Guo ,&nbsp;Shuyan Shi ,&nbsp;Fengyun Yu ,&nbsp;Zongning Chen ,&nbsp;Huijun Kang ,&nbsp;Tongmin Wang","doi":"10.1016/j.jma.2024.03.024","DOIUrl":"10.1016/j.jma.2024.03.024","url":null,"abstract":"<div><div>The development of low-cost, high-performance Mg alloys is crucial to the industrial applications of large-scale production of Mg alloys. In this work, extruded Mg-5Bi-3Al alloy with excellent mechanical properties is successfully prepared by modifying the extrusion temperatures (240 °C and 300 °C). The extruded alloy obtained ultra-high strength (yield strength = 380 MPa, ultimate tensile strength = 418 MPa) and excellent plasticity (elongation = 10.2%) at the extrusion temperature of 240 °C, the main contributing factors are primarily attributed to the synergistic effect of ultrafine recrystallized grain size (∼0.5 µm) and high density of Mg₃Bi₂ precipitates. Stacking faults within the sub-micron Mg₃Bi₂ phase are observed in the E240 alloy, confirming the plastic deformation capability of Mg₃Bi₂ phase. The effects of extrusion temperature on the microstructure, mechanical properties, and work-hardening behavior of the extruded Mg-5Bi-3Al alloys at room temperature are systematically investigated. The results suggest that decreasing the extrusion temperature can refine recrystallized grain size and Mg₃Bi₂ phase size, and the quantity of Mg₃Bi₂ phase is increased, while increasing the extrusion temperature can improve the degree of recrystallization and weaken texture. The work hardening rate is increased with the increased extrusion temperature, mainly due to the coarsening of grains and precipitates, and the weakening of texture. This work provides an experimental basis for preparing high-performance wrought Mg-5Bi-3Al alloys.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 810-822"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141849693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biodegradable Mg-Ca/Mg-Cu bilayer membranes with enhanced mechanical, osteogenesis and antibacterial performances for GBR applications","authors":"Yanbo Shan ,&nbsp;Bo Qiao ,&nbsp;Sihui Ouyang ,&nbsp;Chengao Du ,&nbsp;Lisheng Zhao ,&nbsp;Gang Wang ,&nbsp;Jianting Ye ,&nbsp;Yingjie Xiong ,&nbsp;Yu Wei ,&nbsp;Jiangfeng Song ,&nbsp;Jia She ,&nbsp;Jiang Peng ,&nbsp;Xianhua Chen ,&nbsp;Fusheng Pan ,&nbsp;Ning Wen","doi":"10.1016/j.jma.2024.01.034","DOIUrl":"10.1016/j.jma.2024.01.034","url":null,"abstract":"<div><div>Magnesium (Mg) alloys with biodegradability and excellent mechanical properties are in high demand for applications in guided bone regeneration (GBR). However, the clinical application of Mg alloys is hindered by infection risks and limited osteogenesis. Herein, a structure-functional integrated Mg-Ca/Mg-Cu bilayer membrane was rolled at 150 °C through various single-pass reductions by using online heating rolling. The Mg-Cu layer was specifically engineered to exhibit antibacterial properties tailored for gingival tissue, while the Mg-Ca layer was designed to support bone regeneration within the defect cavity. The bilayer membrane demonstrated a flexural yield strength of 421.0 MPa and a modulus of 58.6 GPa, indicating exceptional deformation resistance. Furthermore, it maintained notable structural stability by retaining 86.4% of its volume after 21 days in Hanks' solution. In vitro results revealed that the bilayer membrane exhibited favorable biocompatibility and promoted osteogenesis via the synergetic effect of released Mg²⁺ and Ca²⁺ ions. The rapid release of Cu²⁺ ions and the creation of an alkaline environment further improved antibacterial properties, potentially preventing postoperative infections. Additionally, in an in vivo rat calvarial defect model, the membrane demonstrated its capability to stimulate new bone formation. In summary, the Mg-Ca/Mg-Cu bilayer membrane exhibited outstanding mechanical stability, favorable corrosion rates, extraordinary osteogenic and antibacterial activity simultaneously. Consequently, it holds promise as a robust barrier membrane in GBR applications.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 792-809"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139943482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flash-PEO of magnesium: Phosphate precursor driven functionalization","authors":"M.H. Guerra-Mutis,&nbsp;J.M. Vega,&nbsp;M.I. Barrena,&nbsp;E. Matykina,&nbsp;R. Arrabal","doi":"10.1016/j.jma.2025.01.007","DOIUrl":"10.1016/j.jma.2025.01.007","url":null,"abstract":"<div><div>In this study, a phosphate-based conversion coating (PCC) was applied as a precursor before forming silicate-fluoride (SiF) and silicate-phosphate-fluoride (SiPF) based flash-plasma electrolytic oxidation (Flash-PEO) coatings on AZ31B magnesium alloy. The main novelty is the successful incorporation of calcium, zinc, manganese and phosphate species into the Flash-PEO coatings via a precursor layer rather than using the electrolyte. The precursor also led to longer lasting and more intense discharges during the PEO process, resulting in increased pore size. Corrosion studies revealed similar short-term performance for all coatings, with impedance modulus at low frequencies above 10⁷ Ωcm², and slightly better performance for the SiPF-based coating. Nonetheless, the enlarged pores in the PEO coatings functionalized with the PCC precursor compromised the effectiveness of self-healing mechanisms by creating diffusion pathways for corrosive species, leading to earlier failure. These phenomena were effectively monitored by recording the open circuit potential during immersion in 0.5 wt.% NaCl solution. In summary, this study demonstrates that conversion coatings are a viable option for the functionalization of PEO coatings on magnesium alloys, as they allow for the incorporation of cationic and other species. However, it is crucial to maintain a small pore size to facilitate effective blockage through self-healing mechanisms.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 592-612"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143072180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atomistic simulations of twin facets associated with three-dimensional {1¯011} twins in magnesium","authors":"Qiyu Zeng ,&nbsp;Mingyu Gong ,&nbsp;Houyu Ma ,&nbsp;Yao Shen ,&nbsp;Jian-feng Nie ,&nbsp;Jian Wang ,&nbsp;Yue Liu","doi":"10.1016/j.jma.2023.07.004","DOIUrl":"10.1016/j.jma.2023.07.004","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Twinning is a deformation mechanism that creates three-dimensional (3D) twin domains through the migration of twin facets. This occurs via the nucleation and glide of twinning disconnections (TDs), which can pile up to create twin facets. A comprehensive understanding of twin facets associated with 3D twins, including their atomic structures and energies, is crucial for understanding deformation twinning. In this study, we propose a molecular statics/dynamics (MS/MD) approach to determine characteristic twin facets enclosing 3D non-equilibrium/equilibrium {&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;011&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;} twin domains, which has been much less studied than the counterpart {&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;012&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;} twin domains. The stability of different TD pile-up arrangement with varying line senses informs the morphology of 3D non-equilibrium twins, which are bounded by {&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;}&lt;sub&gt;T&lt;/sub&gt;||{&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;013&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;}&lt;sub&gt;M&lt;/sub&gt;, {&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;}&lt;sub&gt;T&lt;/sub&gt;||{0002}&lt;sub&gt;M&lt;/sub&gt; and {&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;}&lt;sub&gt;T&lt;/sub&gt;||{&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;}&lt;sub&gt;M&lt;/sub&gt; coherent facets associated with pile-up of edge TDs, and discrete non-edge TDs aligned along CTBs with their line senses parallel to &lt;&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;13&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;&gt;, &lt;&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;01&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;&gt;, &lt;&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;&gt; &lt;&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;&gt;or &lt;&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;&gt; axes. Formation of semi-coherent facets of equilibrium twins is accompanied by rearrangement of TDs around misfit dislocations. 3D equilibrium {&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;011&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;} twins may comprise {&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;}&lt;sub&gt;T&lt;/sub&gt;||{0002}&lt;sub&gt;M&lt;/sub&gt;, {&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;14&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;7&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;}&lt;sub&gt;T&lt;/sub&gt;||{&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;19&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;}&lt;sub&gt;M&lt;/sub&gt;, {&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mover&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;mover&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;mo&gt;¯&lt;/mo&gt;&lt;/mover&gt;&lt;mn&gt;7&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 626-639"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42029085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Loading path and strain rate effects on the deformation behavior of [0001] textured nanocrystalline magnesium: An atomic-scale investigation","authors":"Hui Zhao ,&nbsp;Xuejian Yang ,&nbsp;Yan Peng ,&nbsp;Lu Wu ,&nbsp;Yu Wu ,&nbsp;Baodong Shi","doi":"10.1016/j.jma.2024.03.018","DOIUrl":"10.1016/j.jma.2024.03.018","url":null,"abstract":"<div><div>Molecular dynamics (MD) simulation is employed to investigate the deformation behavior under various loading paths and strain rates of nanocrystalline magnesium (NC Mg) with [0001] texture. Atomic-scale structural evolution of NC Mg was performed under uniaxial and biaxial loadings. In tension process, compression twins and basal slip dominate, while the compression process is dominated by tension twins. The activation mechanism of twinning is highly sensitive to the loading path and grain orientation. Meanwhile, the effect of strain rate on the structural evolution of NC Mg was investigated. It is found that the effect of strain rate on the plastic deformation of NC Mg is reflected through the plasticity delays and the way to release the stress. As the strain rate decreases, the plastic deformation mechanism gradually changes from intragranular to grain boundary. Some significant potential deformation mechanisms in the loading process were studied. It is observed that {<span><math><mrow><mn>11</mn><mover><mn>2</mn><mo>¯</mo></mover><mn>1</mn></mrow></math></span>} twins nucleated inside the grains, and the thickening process is completed by basal 〈a〉 slip of the twin boundary. The strain compatibility between twins is automatically optimized with loading. Moreover, the detwinning mechanism caused by the interaction between twins and basal stacking faults is clarified.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 839-857"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140762133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure and mechanical properties with different sintering temperature of AZ91D alloy","authors":"Limin Li ,&nbsp;Huanqing Li ,&nbsp;Pengya Lei ,&nbsp;Wei Liu ,&nbsp;Liwen Chen ,&nbsp;Hua Hou ,&nbsp;Yuhong Zhao","doi":"10.1016/j.jma.2024.01.024","DOIUrl":"10.1016/j.jma.2024.01.024","url":null,"abstract":"<div><div>The regulation of sintering temperature in spark plasma sintering enables the achievement of grain refinement, phase control, and performance enhancement in the preparation of AZ91D magnesium alloy. This study investigates the influence of sintering temperature on microstructural evolution and mechanical properties of the AZ91D alloy. Microstructural analysis was conducted using scanning electron microscopy, electron backscatter diffraction, and X-ray diffraction. Microscopic structures and mechanical behaviors were examined through hardness and tensile tests. Elevated sintering temperatures resulted in reduced secondary phase content, leading to a decrease in mechanical performance. The alloy exhibited optimal mechanical properties at 320°C. The nanoparticle coarsening process and particle evolution during sintering were simulated using phase field methods. By optimizing the sintering temperature, precise control over microstructural and textural evolution can be achieved, facilitating the attainment of desired hardness levels and mechanical properties.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 697-708"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139574073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transmutation of zonal twinning dislocations during non-cozone {101¯1} twin-twin interaction in magnesium","authors":"Peng Chen ,&nbsp;Bin Li","doi":"10.1016/j.jma.2024.01.032","DOIUrl":"10.1016/j.jma.2024.01.032","url":null,"abstract":"<div><div>Theoretically, a twinning dislocation must stay on the twinning plane which is the first invariant plane of a twinning mode, because the glide of twinning dislocation linearly transforms the parent lattice to the twin lattice. However, recent experimental observations showed that a <span><math><mrow><mrow><mo>{</mo><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>1</mn></mrow><mo>}</mo></mrow><mrow><mo>〈</mo><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mover><mn>2</mn><mo>¯</mo></mover></mrow><mo>〉</mo></mrow></mrow></math></span> twin variant could cross another variant during twin-twin interaction. It is well known that <span><math><mrow><mo>{</mo><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>1</mn></mrow><mo>}</mo></mrow></math></span> twinning is mediated by zonal twinning dislocations. Thus, how the zonal twinning dislocations transmute during twin-twin interaction is of great interest but not well understood. In this work, atomistic simulation is performed to investigate interaction between <span><math><mrow><mo>{</mo><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>1</mn></mrow><mo>}</mo></mrow></math></span> twin variants. Our results show that when an incoming twin variant impinges on the other which acts as a barrier, surprisingly, the barrier twin can grow at the expense of the incoming twin. Eventually one variant consumes the other. Structural analysis shows that the twinning dislocations of the barrier variant are able to penetrate the zone of twin-twin intersection, by plowing through the lattice of one variant and transform its lattice into the lattice of the other. Careful lattice correspondence analysis reveals that, the lattice transformation from one variant to the other is close to <span><math><mrow><mrow><mo>{</mo><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>2</mn></mrow><mo>}</mo></mrow><mrow><mo>〈</mo><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mover><mn>1</mn><mo>¯</mo></mover></mrow><mo>〉</mo></mrow></mrow></math></span> twinning, but the orientation relationship deviates by a minor lattice rotation. This deviation presents a significant energy barrier to the lattice transformation, and thus it is expected such a twin-twin interaction will increase the stress for twin growth.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 681-696"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139917076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the theoretical and mechanism of CaF₂-catalyzed vacuum carbothermal reduction of MgO","authors":"Tingzhuang Ma ,&nbsp;Bin Yang ,&nbsp;Yang Tian ,&nbsp;Neng Xiong ,&nbsp;Baoqiang Xu ,&nbsp;Guozheng Zha ,&nbsp;Rong Yu ,&nbsp;Dong Liang ,&nbsp;Lipeng Wang ,&nbsp;Dong Wang","doi":"10.1016/j.jma.2024.06.020","DOIUrl":"10.1016/j.jma.2024.06.020","url":null,"abstract":"<div><div>The increasing demand for magnesium as a next-generation structural material highlights the significance of incorporating CaF₂ as a catalyst to enhance the efficiency of vacuum carbothermal reduction of magnesium (VCTRM). This study investigates the thermodynamic theory and catalytic mechanism of CaF₂ in the VCTRM process. Catalytic reduction experiments and molecular dynamics simulations were conducted to gain a comprehensive understanding of the process. Thermodynamic calculations indicate that in vacuum carbothermal reduction, the primary reaction occurs between MgO and C. Analysis shows that CaF₂'s catalytic action primarily involves F⁻, Ca²⁺, and melt eutectic. Our experiments demonstrate that the addition of CaF₂ significantly increases the reduction rate. Furthermore, the mass loss rate increases with both the quantity of CaF₂ added and the holding time, stabilizing at additions over 5%. Experiments conducted at temperatures above the melting point of CaF₂ exhibited a pronounced catalytic effect. The resultant magnesium showed optimal structure and crystallization, with a purity of 87.84%. Notably, while CaF₂ remained in the residue, it was not detected in the condensate, confirming its catalytic role. Molecular dynamics simulations revealed that molten CaF₂ sabotages the structure of magnesium oxide, with F⁻ dispersing onto the surface of MgO, thus enhancing the reaction between MgO and C to form CO. However, no chemical reaction was observed between C, MgO, and CaF₂. The occurrence of the carbothermal reduction reaction at high temperatures depends on the concentration of the reducing agent C, with CaF₂ influencing the reaction rate. This research elucidates the theoretical and mechanistic foundations of CaF₂-catalyzed VCTRM, aligning with the green energy-saving concept and significantly advancing the green and efficient VCTRM process.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 731-745"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141703942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Creep properties and fracture behavior of AZ31B extruded sheets with mixed-grain microstructures of different morphologies","authors":"Xiaoxia Zhang ,&nbsp;Ming Li ,&nbsp;Hongxia Wang ,&nbsp;Jiao Cui ,&nbsp;Lei Song ,&nbsp;Naidong Ren ,&nbsp;Lifei Wang ,&nbsp;Weili Cheng ,&nbsp;Kwangseon Shin","doi":"10.1016/j.jma.2024.08.013","DOIUrl":"10.1016/j.jma.2024.08.013","url":null,"abstract":"<div><div>In this work, AZ31B extruded sheets with mixed-grain microstructures were prepared through extrusion. Samples of mixed-grain microstructure with different morphologies were selected from the AZ31B extruded sheets (referred to as M1 and M2 samples, respectively). The creep tests were performed on these samples at the temperature range of 150–200 °C, and the stress level range of 50–100 MPa. The creep properties and fracture behavior of AZ31 extruded sheets with mixed-grain microstructures were studied. Results showed that the creep properties of the M2 sample always outperformed that of the M1 sample and M1 and M2 samples’ creep was dominated by dislocation movement. The creep rate of M2 samples (1.5 × 10^-7 ± 1.1 × 10^-10 s^-1) is an order of magnitude lower than that of M1 samples (4.8 × 10^-6 ± 8.1 × 10^-10 s^-1) at 200 °C under 50 MPa The high activity of basal slip and softening mechanism in the M1 sample significantly accelerated creep, resulting in a relatively high creep rate. Moreover, the stress concentration within the M1 sample caused by deformation incompatibility, increased the initiation and propagation of voids, ultimately leading to fracture and poorer creep performance. However, the numerous &lt;10 µm fine grains surrounding deformed coarse grains in the M2 sample facilitated better coordination of deformation through dislocation slip, effectively slowing down the initiation of voids during the creep process. Meanwhile, the strain was uniformly distributed within each grain, mitigating stress concentration, inhibiting voids propagation, and contributing to the superior creep resistance of the M2 sample.</div></div>","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"13 2","pages":"Pages 777-791"},"PeriodicalIF":15.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143550842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}