Journal of Alloys and Metallurgical Systems最新文献

{"title":"Coupled oxidation and solidification control in wire-arc deposited Mg–Gd–Y–Zr alloy through local shielding and polarity modulation","authors":"Haiou Yang,&nbsp;Kuitong Yang,&nbsp;Lingming Kong,&nbsp;Xin Lin,&nbsp;Wenzhe Yang","doi":"10.1016/j.jalmes.2026.100273","DOIUrl":"10.1016/j.jalmes.2026.100273","url":null,"abstract":"<div><div>Oxide entrainment and uncontrolled thermal histories limit open-arc deposition of reactive magnesium–rare-earth (Mg–RE) alloys. Here, Mg–9.54Gd–1.82Y–0.44Zr wire was deposited by wire-arc additive manufacturing (WAAM) using cold metal transfer (CMT), local trailing Ar shielding, and CMT-Advance polarity modulation. Relative to unprotected deposition, porosity decreased from 0.065% to 0.040%, while the X-ray computed tomography (CT)-detectable oxide-related defect fraction decreased from 0.02300% to 0.00047%. A three-dimensional arch-bead heat-transfer model was calibrated against complete thermocouple histories. Peak-temperature errors were 0.09–1.07%, and 0–100 s root-mean-square errors (RMSEs) were 3.37–10.02 °C. Model-consistent net heat inputs were 226.7, 103.9, 113.9, and 107.1 J mm⁻¹ for CMT and CMT-Advance positive-electrode/negative-electrode (EP/EN) ratios of 0, 1, and 5, respectively. CMT-Advance increased the thermal gradient (G) and cooling intensity at the stable section, while the ratio of thermal gradient to interface velocity (G/R) increased strongly towards the substrate. Electron backscatter diffraction (EBSD) showed weak textures and a representative minimum mean grain size under EP/EN = 0. X-ray diffraction (XRD) was dominated by α-Mg and contained weak reflections indexed to Mg₂₄(Gd,Y)₅. Scanning electron microscopy (SEM) of the fracture surfaces showed dimpled rupture in all conditions, with a more uniform ductile morphology after shielding. The shielded CMT-Advance condition achieved 154.8 ± 2.8 MPa yield strength, 250.6 ± 0.9 MPa ultimate tensile strength, and 10.0 ± 0.2% elongation. These results separate oxygen-supply control from polarity-dependent heat input and residual-film transport within a process–microstructure–property framework.</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"15 ","pages":"Article 100273"},"PeriodicalIF":4.8,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148958899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine learning-driven prediction of phase transformation regions of TTT diagram for carbon and low alloy steels via high-throughput boosting methods","authors":"Atul Srivastava,&nbsp;Suresh Kant Verma,&nbsp;Amar Nath Sinha","doi":"10.1016/j.jalmes.2026.100264","DOIUrl":"10.1016/j.jalmes.2026.100264","url":null,"abstract":"<div><div>Time–temperature-transformation (TTT) diagrams are essential for describing isothermal phase transformation kinetics in carbon and low-alloy steels and for designing heat-treatment schedules. However, their experimental construction requires extensive metallographic characterization over wide temperature–time domains, limiting rapid compositional screening. In this study, ensemble boosting algorithms were systematically evaluated for predicting four critical phase boundaries: Pearlite Start (Ps), Pearlite End (Pe), Bainite Start (Bs), and Bainite End (Be). A dataset comprising 93 experimentally reported TTT diagrams was digitized and preprocessed using strict correlation filtering and normalization procedures. Independent regression models were developed with 10-fold cross-validation and evaluated using both conventional random splitting and a stricter steel-wise compositional split strategy to assess generalization across unseen steel compositions. Among the studied models, including AdaBoost, Gradient Boosting, LightGBM, XGBoost, and CatBoost, the CatBoost model exhibited the most consistent performance, achieving (R² <span><math><mo>≥</mo></math></span> 0.97 for pearlitic transformations (RMSE as low as 12<!--> <!-->°C) and stable accuracy for bainitic regions (RMSE <span><math><mo>≈</mo></math></span> 22<!--> <!-->°C). SHAP analysis identified transformation time, carbon, and nickel as dominant predictors, consistent with established transformation theory. The model was further validated using a steel-wise compositional split, and TTT curves for 15 independent (unseen) steel compositions were predicted. Validations against experimentally reported TTT diagrams demonstrate strong agreement between reconstructed and reported TTT curves, including accurate prediction of the transformation nose. These results demonstrate that boosting-based models provide an accurate and interpretable framework for rapid estimation of TTT diagrams, thereby helping to reduce experimental effort and supporting alloy and heat-treatment design</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"15 ","pages":"Article 100264"},"PeriodicalIF":4.8,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148958898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gallium-alloyed metastable β Ti–Zr–Nb–Sn–Ta alloys with balanced mechanical, corrosion, and dual antibacterial–osteoblastic cytocompatibility for orthopedic implants","authors":"Deqiang Ma ,&nbsp;Qianqiu Du ,&nbsp;Zhixin Li ,&nbsp;Ruonan Jiao ,&nbsp;Shaoqiang Yuan","doi":"10.1016/j.jalmes.2026.100255","DOIUrl":"10.1016/j.jalmes.2026.100255","url":null,"abstract":"<div><div>Stress shielding and implant-associated infection are the primary causes of orthopedic implant failure. Low-modulus metastable <em>β</em>-Ti alloys are promising implant candidates, yet face the key challenge of balancing mechanical, corrosion-related, and biological properties. Herein, we developed a series of Gallium (Ga)-alloyed metastable <em>β</em> Ti-Zr-Nb-Sn-Ta (TZNST) alloys, and systematically investigated the effects of Ga content (0–2.5 at%, denoted as TZNST-Ga_<em>x</em>) on their microstructure, mechanical attributes, corrosion performance, and <em>in vitro</em> cytocompatibility and antibacterial efficacy. All as-cast TZNST-based alloys exhibited a single metastable <em>β</em>-phase structure, with Ga addition inducing fine dendritic structures. The TZNST-based alloys achieved a maximum 22% yield strength increment (638.3–780.7 MPa), approximately 50% compressive plasticity without catastrophic fracture, and a low elastic modulus (58.1–63.7 GPa). Among the series, TZNST-Ga_2.0 delivered the optimal comprehensive performance: it exhibited a 3.7-fold higher polarization resistance than the base alloy (TZNST-Ga_0.0) in Hanks’ Balanced Salt Solution (HBSS), a MC3T3-E1 cell viability of &gt; 98%, and an inhibition rate of 88.80% against <em>Escherichia coli</em> (<em>E</em>. <em>coli</em>) and 85.12% against <em>Staphylococcus aureus</em> (<em>S. aureus</em>). The antibacterial efficacy of the Ga-containing TZNST alloys arises primarily from the sustained release of Ga^3 + ions from the passive film. This system possesses pH-responsive Ga³⁺ ion release behavior. The release of Ga³⁺ ions is remarkably promoted under acidic microenvironments, which endows the system with microenvironment-targeted antibacterial capability. It can be concluded that this class of Ga-alloyed <em>β</em>-Ti alloys can address two important clinical problems regarding orthopedic implants, representing a promising strategy for developing multifunctional biomedical titanium materials.</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"14 ","pages":"Article 100255"},"PeriodicalIF":0.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148167788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quenched and auto-tempered high-strength reinforcing steel rebars for corrosion-sensitive areas","authors":"M.A. Islam,&nbsp;Md. Nazmul Ahsan Dipon,&nbsp;Md. Tarif","doi":"10.1016/j.jalmes.2026.100254","DOIUrl":"10.1016/j.jalmes.2026.100254","url":null,"abstract":"<div><div>Corrosion is the primary barrier for reduced safe service life of any reinforced concrete (RC) structure, particularly in the chloride-rich marine environment. Quenched and auto-tempered (QAT) reinforcing steel rebars offer superior strength and cost advantages over hot-rolled and normalized (HRN) counterparts, yet their corrosion susceptibility in aggressive environments remains a critical limitation. This study systematically investigates the corrosion behaviour of QAT (75 G) and HRN (60 G) steel rebars through a comprehensive experimental program. Microstructural characterization using optical microscopy revealed distinct case-core structures in QAT steels, which is absent in HRN steels. Tensile testing confirmed compliance with BDS ISO 6935–2:2021 standards for all grades. To evaluate corrosion behaviour, reinforced concrete specimens were cast, water-cured for 28 days, and subsequently exposed to a 3 wt% NaCl solution for up to 10 weeks. Corrosion performance was evaluated through macrocell corrosion current measurements, complemented by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP). Post-exposure surface morphology analysis and Fourier Transform Infrared spectroscopy (FTIR) of corrosion products provided further mechanistic insight. X-ray diffraction (XRD) analysis revealed significantly higher compressive residual stress and microstrain in QAT steels, which showed strong linear correlations with corrosion current. Controlled additions of Cu, Cr, and Ni progressively modified rust layer and interface characteristics, consequently reducing corrosion current in QAT steels, with the best-performing alloy (75G-4: 0.15%Ni, 0.18%Cr, 0.18%Cu) achieving corrosion resistance comparable to HRN steel at only a ∼5% cost increase. These findings demonstrate a practical cost-effective pathway toward high-strength, corrosion-resistant QAT rebars for durable RC structures in marine environments.</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"14 ","pages":"Article 100254"},"PeriodicalIF":0.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148167787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Eco-hybrid aluminum composites reinforced with waste-derived Eggshell and Aloe vera for engineering applications","authors":"Md Mahadi Hassan Parvez ,&nbsp;Md. Arafat Islam ,&nbsp;Md. Roknuzzaman ,&nbsp;Tamanna Rahman ,&nbsp;Md Rayhan Amin ,&nbsp;Shawon Ahmmed ,&nbsp;Md Jubair Muin","doi":"10.1016/j.jalmes.2026.100256","DOIUrl":"10.1016/j.jalmes.2026.100256","url":null,"abstract":"<div><div>This research evaluates the fabrication and comprehensive analysis of hybrid aluminum metal matrix composites (AMMCs) reinforced with Aloe vera Powder (AVP) and Eggshell Powder (ESP) using stir casting process. Three different types of composites i.e., AS1 (base sample), AS2, and AS3 were fabricated varying the composition of AVP keeping the composition of ESP fixed. The samples were undergone for different types of tests to determine the properties of the fabricated composites. From the tensile test, it was observed that the reinforcement greatly improved mechanical properties, with the AS2 composition showing the highest tensile strength of 153.61 MPa, a 28% increase from the base sample. SEM micrographs highlighted optimal reinforcement distribution in AS2, with slight agglomeration and micro-void formation in AS3, consistent with slightly reduced strength. EDX analysis confirmed the presence and successful incorporation of O and C elements from ESP and AVP, respectively. FTIR and XRD spectra demonstrated the retention of functional groups and stable FCC crystal structure with sharpened peaks in the reinforced samples. DTG and DSC studies confirmed improved thermal stability and heat absorption capacity of the hybrid samples, especially AS2. Density measurements exhibited increments with the addition of ESP and efficient particle arrangement. Hardness measurements evaluated significant increases from AS1 to AS3. This work proves that the combined ESP and AVP reinforcement was needed for the production of a low-cost and high-performance eco-friendly composites for engineering applications, wherein optimal filler proportions can be improved mechanical, physical and thermal properties of aluminum composites.</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"14 ","pages":"Article 100256"},"PeriodicalIF":0.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148231218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Allotropic α→β transformation in diffusion-graded commercial-purity Ti–Zr multilayers: DSC overlapping peak deconvolution and kissinger kinetic analysis","authors":"Anas Jawabreh,&nbsp;Péter Barkóczy","doi":"10.1016/j.jalmes.2026.100238","DOIUrl":"10.1016/j.jalmes.2026.100238","url":null,"abstract":"<div><div>Multilayered Ti–Zr mesostructures were produced from commercially pure Ti and Zr by subsequent hot compression and heat treatment then annealed at 740 °C and 770 °C for 120 h to generate a near-continuous Ti-rich to Zr-rich concentration gradient. Differential scanning calorimetry (DSC) was used to examine the α→β transformation at heating rates of 10–25 K/min, supported by optical microscopy and SEM–EDS to assess the extent of diffusion. The first endothermic reaction starts near the ∼50–50 at% Ti-Zr region where the transformation temperature is lowest according to the published and Thermo-calc calculated phase diagrams, while subsequent reactions occur in adjacent Ti- and Zr-rich compositions, producing strongly overlapping peaks in a small temperature range. The low-temperature peak ranges occur at 549.9 °C −562.1 °C and 570.4 °C −576.6 °C after 740 °C annealing, and at 543.5 °C −589.3 °C and 584.6 °C −645.3 °C after 770 °C annealing, followed by a high-temperature β-completion peak at 838 °C −867.6 °C (740 °C) or 915 °C −926.8 °C (770 °C). A Savitzky–Golay filtering, derivative-based segmentation, and Avrami-type deconvolution were used to isolate the overlapping reactions, and Kissinger analysis of the deconvoluted peaks provided apparent activation energies for each step. For the 740 °C samples, the first two low-temperature (onset) steps show higher apparent activation energies (225.7 and 474.7 kJ·mol⁻¹) than the β-completion step (163.145 kJ·mol⁻¹), while for the 770 °C samples the trend reverses (74.5 and 60.1 kJ·mol⁻¹ vs. 676.3 kJ·mol⁻¹). This change in trend indicates that diffusion heat treatment changes the gradient geometry, which controls peak overlap and shifts the apparent kinetics from deconvolution.</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"13 ","pages":"Article 100238"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147384651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Er addition and thermomechanical processing on the in vitro corrosion and cytocompatibility of Mg–Zn–Y alloys","authors":"Raisa Tahsin Promy ,&nbsp;Md. Walid Ahmed Nafiz ,&nbsp;Syed Muhammad Al Amin ,&nbsp;Chanchal Kumar Roy ,&nbsp;Fahmida Gulshan","doi":"10.1016/j.jalmes.2026.100233","DOIUrl":"10.1016/j.jalmes.2026.100233","url":null,"abstract":"<div><div>Controlling the corrosion rate of magnesium-based biodegradable alloys remains a key challenge for biomedical applications. This study investigates the effect of Er addition and thermomechanical processing (rolling and extrusion) on the cytocompatibility and corrosion behavior of Mg-1.88Zn-0.58Y alloys. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and optical microscopy (OM) identified the presence of secondary phases such as Mg<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>Zn and W-phases in both alloys and Mg₂₄Er₅ only in the Mg-1.81Zn-0.8Y-0.33Er alloy. Corrosion behavior was evaluated by immersion tests in periodically replenished Kokubo’s simulated body fluid (SBF) for up to 21 days, with continuous pH monitoring. Hydrogen evolution tests, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS) supported the immersion findings, and post-corrosion SEM-EDS and Fourier-transform infrared spectroscopy (FTIR) analyses elucidated the underlying reasons. In both alloys, hot extrusion enhanced the formation of a protective Mg(OH)<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> layer and reduced the corrosion rate. The extruded Mg-1.88Zn-0.58Y alloy exhibited the lowest weight-loss rate (14.45 to 9.79 mm year⁻¹ from day 1 to day 21), hydrogen release (<span><math><mo>∼</mo></math></span>2.9 mL cm<span><math><msup><mrow></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup></math></span> d<span><math><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span>), and corrosion current density (<span><math><mrow><mn>31</mn><mo>.</mo><mn>58</mn><mspace></mspace><mi>μ</mi><mi>A</mi></mrow></math></span> cm⁻²). The Er-containing alloy showed poor corrosion resistance in the as-cast and rolled states (45.96 and 38.88 mm year⁻¹ after 21 days, respectively), but significant improvement in the extruded condition (10.04 mm year⁻¹). Er containing quaternary alloys exhibited much higher H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> evolution rate of <span><math><mo>∼</mo></math></span>17.2 mL cm<span><math><msup><mrow></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup></math></span> d<span><math><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> (after 24 h) for the as cast sample, considerably more than the acceptable limit for human body. Overall, the Er addition to the ternary alloy resulted in poor corrosion resistance. MTT cytotoxicity assays on Vero cells confirmed non-cytotoxic behavior (<span><math><mo>&gt;</mo></math></span>95% viability), while the Er-containing Mg-1.81Zn-0.8Y-0.33Er alloy extract produced strong selective toxicity against HeLa cells (<span><math><mo>&lt;</mo></math></span>5% viability).</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"13 ","pages":"Article 100233"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-temperature cyclic oxidation and microstructural behavior of CoMoCrSi-based composite coatings with Al2O3 and YSZ on T91 steel","authors":"Rakshith Kumar Shetty ,&nbsp;Ajit M. Hebbale ,&nbsp;T.V. Chandramouli ,&nbsp;M.R. Ramesh ,&nbsp;Jana Petru","doi":"10.1016/j.jalmes.2026.100232","DOIUrl":"10.1016/j.jalmes.2026.100232","url":null,"abstract":"<div><div>This investigation focuses on the cyclic oxidation behaviour and microstructural evolution of Cobalt-Molybdenum-Chromium-Silicon coatings reinforced with alumina and yttria stabilised zirconia (YSZ) deposited on T91 steel by the atmospheric plasma spraying method. Characterization of the as-sprayed coatings was done to provide a consistent base line for comparison of the intercoatings. Cyclic oxidation experiments at 800 °C for 50 oxidation cycles was carried out with surface and cross section analyses using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) for the evaluation of oxidation scale formation, element distribution and phase stability. After cyclic oxidation, XRD showed an appearance of stable oxide constituents, which demonstrates the formation of protective scales on the coating surfaces. In comparison with unreinforced and alumina reinforced coatings, the YSZ reinforced coating displayed comparatively superior oxidation behavior as reflected in the more stable oxidation and less degradation during cyclic exposure. SEM examination of oxidized surfaces showed that the ceramic additions helped to increase coating integrity, improve scale adherence and reduce oxygen penetration. These effects were amplified for the YSZ-containing coating, showing a good response for high temperature oxidation. Overall, the addition of ceramic reinforcements, especially of YSZ, improved the phase stability and oxidation resistance of the CoMoCrSi-based coatings, which supports the suitability of the coatings for demanding boiler environments.</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"13 ","pages":"Article 100232"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145926083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Sn addition on the microstructure, mechanical properties, and corrosion behaviour of AZ31 magnesium alloy","authors":"Md. Rakibul Islam ,&nbsp;Istiak Mahmood Rahi ,&nbsp;Md. Noushad Hossain ,&nbsp;H.M.M. A. Rashed","doi":"10.1016/j.jalmes.2026.100234","DOIUrl":"10.1016/j.jalmes.2026.100234","url":null,"abstract":"<div><div>This study systematically investigates the effect of adding tin (Sn) to AZ31 magnesium alloy on its microstructure, mechanical strength, and corrosion behaviour. Alloys with 0, 2, and 4 wt% Sn were processed and characterized using microscopy, X-ray diffraction, hardness testing, hot compression (at 300 °C), and electrochemical impedance spectroscopy (EIS). Quantitative analysis revealed that Sn addition significantly refined the grain size from 137.8 µm to 23.7 µm and promoted the formation of Mg₂Sn precipitates. Calculations determined that the total strength gain in the AZ31–2 %Sn alloy was overwhelmingly dominated by grain refinement and solid solution effects. In the AZ31–4 %Sn alloy, while grain refinement remained the largest component, the sharp increase in overall strength was substantially augmented by the presence of Mg₂Sn Orowan precipitates. Constitutive analysis of hot deformation yielded strain rate sensitivity exponents (m) between 0.17 and 0.20, identifying dislocation climb as the governing deformation mechanism, with a minor contribution from grain boundary sliding in the fine-grained 4 % Sn alloy. Equivalent circuit modeling of EIS data demonstrated a trade-off in corrosion performance: the 2 % Sn alloy achieved the highest charge-transfer resistance (R_ct ≈ 1.7 ×10^5 Ω). This improvement is specifically attributed to Sn4 + -induced modification of the MgO/Mg(OH)₂ passive film, resulting in a denser and more stable barrier. Conversely, the 4 % Sn alloy suffered from accelerated degradation (R_ct ≈ 2.05 ×10^4 Ω) because excessive Sn forms coarse Mg₂Sn intermetallics, which act as cathodic sites and drive micro-galvanic corrosion. These findings highlight that moderate Sn alloying (2 wt%) optimizes the property balance by enhancing strength without compromising corrosion resistance.</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"13 ","pages":"Article 100234"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146173429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An attempt toward machine learning-driven optimization of manufacturing processes for metal-supported solid oxide fuel cells using nickel and iron oxides as raw support materials","authors":"Hirofumi Sumi ,&nbsp;Mizuki Momai ,&nbsp;Yuki Yamaguchi","doi":"10.1016/j.jalmes.2025.100230","DOIUrl":"10.1016/j.jalmes.2025.100230","url":null,"abstract":"<div><div>A novel fabrication method for metal-supported solid oxide fuel cells (SOFCs) is proposed using nickel and iron oxides as raw support materials. This approach enables the co-sintering of all components in their oxide states via conventional ceramic processing. To minimize cell warpage, which is a critical issue in mechanical integrity, machine learning models, including random forest and linear regression, are employed to optimize the manufacturing process parameters. The random forest regression model demonstrated superior predictive accuracy (RMSE = 0.01454 and <em>R</em>² = 0.7310) than the linear regression model (RMSE = 0.02253 and <em>R</em>² = 0.4642), effectively capturing the non-linear relationships between the manufacturing process parameters and cell warpage. The electrolyte thickness, presintering temperature, and Ni/(Fe+Ni) atomic ratio are identified as key factors influencing cell warpage. Material characterizations using X-ray diffraction and coefficient of thermal expansion measurements validate these predictions. Although the open circuit voltage remains below the theoretical electromotive force owing to residual microstructural defects in the electrolyte, the cell warpage successfully reduced from 0.07578 to 0.03825 by increasing the presintering temperature from 1150 to 1250 °C. These results demonstrate the potential of machine learning for guiding manufacturing process optimization of mechanically robust and high-performance metal-supported SOFCs.</div></div>","PeriodicalId":100753,"journal":{"name":"Journal of Alloys and Metallurgical Systems","volume":"13 ","pages":"Article 100230"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145738965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}