Acta Materialia最新文献

{"title":"Temperature and misorientation-dependent austenite nucleation at ferrite grain boundaries in a medium manganese steel: role of misorientation-dependent grain boundary segregation","authors":"Rama Srinivas Varanasi ,&nbsp;Osamu Waseda ,&nbsp;Faisal Waqar Syed ,&nbsp;Prithiv Thoudden-Sukumar ,&nbsp;Baptiste Gault ,&nbsp;Jörg Neugebauer ,&nbsp;Dirk Ponge","doi":"10.1016/j.actamat.2025.121242","DOIUrl":"10.1016/j.actamat.2025.121242","url":null,"abstract":"<div><div>In the current work, we study the role of grain boundary (GB) misorientation-dependent segregation on austenite nucleation in a 50 % cold rolled intercritically annealed 10Mn-0.05C-1.5Al (wt. %) medium Mn steel. During intercritical annealing at 500 °C, austenite nucleates predominantly at high-angle GBs. At 600 °C, austenite nucleates additionally at low-angle GBs, exhibiting a temperature dependance. Correlative transmission Kikuchi diffraction /atom probe tomography reveals a misorientation-dependent segregation. While GB segregation has been reported to assist austenite nucleation in medium manganese steels (3–12 wt. % Mn), an understanding of the temperature and misorientation dependance is lacking, which is the aim of current work. Since artifacts of the atom probe can cause a broadening of the segregation width, we combined experiments with results from density functional theory (DFT) calculations that reveal that the Mn segregation is not limited to the GB plane but confined to a region in the range of approximately 1 nm. Consequently, GB segregation alters both the GB interface energy and the free energy per unit volume corresponding to the transformation. We estimate the local driving force for austenite nucleation accounting for the segregation width. Based on classical nucleation theory, we clarify the effect of GB segregation on the critical radius and activation energy barrier for confined austenite nucleation at the GB.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121242"},"PeriodicalIF":8.3,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144252744","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":"Atomic-scale features of phase interfaces in Sm(CobalFe0.09Cu0.09Zr0.03)7.24 sintered magnets and their potential roles","authors":"Yingchang Li ,&nbsp;Minggang Zhu ,&nbsp;Nengjun Yu ,&nbsp;Yikun Fang ,&nbsp;Zhongxin An ,&nbsp;Boxi Zhang ,&nbsp;Chao Wang ,&nbsp;Wei Li","doi":"10.1016/j.actamat.2025.121230","DOIUrl":"10.1016/j.actamat.2025.121230","url":null,"abstract":"<div><div>In this study, the atomic-scale microstructures of phase interfaces in Sm(Co_balFe_0.09Cu_0.09Zr_0.03)_7.24 sintered magnets were observed and analyzed, and two new types of microstructure features were found. First, the extension region (the region where 1:5H cell boundary expands outward) was observed at the junction of the three phases (2:17R cell, 1:5H cell boundary, and lamellar phases). The microstructural analysis revealed that the Co dumbbells in the 2:17R cell phase are replaced by Sm, leading to the transformation of part of the 2:17R cell phase into the 1:5H cell boundary phase. Second, the Sm concentration gradient transition region (The atomic layer with transitional features between the 2:17R cell and lamellar phases) was observed at the interface between the 2:17R cell and the lamellar phases, formed by the partial replacement of Co dumbbells with Sm. Furthermore, the formation of the aforementioned two features is associated with interface energy and replacement of Sm by Zr resulting from the formation of the lamellar phase. The extension region widens the thickness of the cell boundary phase. Micromagnetic simulation shows that the extension region enhances the pinning strength. The transition region widens the Cu diffusion path, but it may also reduce the substitution energy of Cu in it. This study provides a comprehensive atomic-scale understanding of the complex cellular structure in Sm₂Co₁₇-type magnets.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121230"},"PeriodicalIF":8.3,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144252745","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":"Constructing nanochannels via dense amorphous/crystalline NiFeB/Ni2P heterointerface for ultra-stable oxygen evolution reaction","authors":"Yuhua Liu ,&nbsp;Heng Liu ,&nbsp;Zizhun Wang,&nbsp;Xu Zou,&nbsp;Xingyou Lang,&nbsp;Qing Jiang,&nbsp;Wei Zhang,&nbsp;Weitao Zheng","doi":"10.1016/j.actamat.2025.121238","DOIUrl":"10.1016/j.actamat.2025.121238","url":null,"abstract":"<div><div>The sluggish diffusion of proton acceptors within the interlayers of NiFe-based layered hydroxides leads to structural collapse, which poses a huge challenge for developing high-performance electrode materials in the oxygen evolution reaction (OER). Herein, robust nanochannels were constructed by customizing the amorphous/crystalline heterointerface for ultra-stable alkaline OER. Boronized treatment triggers the formation of a NiFeB amorphous layer coating on the surface of the Ni₂P conductive substrate, creating a high density of nanoscale NiFeB-Ni₂P interface. Such amorphous NiFe hydroxides generated by NiFeB alloying reconstruction caused loose internal structure during electrooxidation, allowing accelerated electrolyte ion transport. The robust amorphous/crystalline nanochannels further facilitate the oxidation of Ni, leading to the generation of more unsaturated Ni^3+δ sites, serving as catalytically active centers for reducing the conversion energy barrier of O intermediates. The architecture of NiFeB@Ni₂P/Ni foam integrated electrode achieves a low overpotential of 277 mV at 100 mA cm⁻² and remarkable stability for 1000 h, highlighting an efficient strategy for improving the operating stability of catalysts.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121238"},"PeriodicalIF":8.3,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144238187","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":"In-situ study of the temperature effects on the magneto-structural transition in the MnCoGe-based magnetocaloric compounds","authors":"Xiaowen Hao ,&nbsp;Ying Zhao ,&nbsp;Xiaoming Huang ,&nbsp;Kang Liu ,&nbsp;Binru Zhao ,&nbsp;Cuiping Zhang ,&nbsp;Jie Ma ,&nbsp;Fengjiao Qian ,&nbsp;Xuefei Miao ,&nbsp;Yafei Kuang ,&nbsp;Haile Yan ,&nbsp;Zongbin Li ,&nbsp;Liang Zuo ,&nbsp;Xin Tong ,&nbsp;Bo Yang ,&nbsp;Qingyong Ren","doi":"10.1016/j.actamat.2025.121241","DOIUrl":"10.1016/j.actamat.2025.121241","url":null,"abstract":"<div><div>The first-order magneto-structural transition with large adiabatic magnetic entropy change shows great potential for magnetocaloric refrigeration but is hindered by large thermal and magnetic hysteresis effects, such as in the MM'X alloys (M, M' = 3d transition element, X = Si, Ge). While progress has been made in reducing thermal hysteresis through improved geometric compatibility, the joint effects of thermal and magnetic hysteresis are not well understood, which is a crucial issue in the practical operation of magnetocaloric refrigeration. In this work, we present an <em>in-situ</em> study of the temperature effects on the magnetic-field-driven magneto-structural transition in MnCoGe-based compounds. Our results show that the metamagnetic transition from paramagnetic hexagonal to ferromagnetic orthorhombic structures is more easily driven by an external magnetic field during cooling compared to heating. The magnetization loop exhibits larger hysteresis losses during cooling, while the magneto-structural transition temperature determined from iso-field magnetizations is more affected by the magnetic field. Additionally, the negative thermal expansion behavior displays a more uniform distribution within the entire phase transition temperature window during cooling. <em>In-situ</em> X-ray diffraction measurements and geometric nonlinear theory analysis suggest that those discrepancies during heating and cooling originate from smaller lattice geometric incompatibilities, particularly along the <em>a</em>-axis of the orthorhombic structure. Furthermore, it is found that the transformation stretch tensor eigenvalues exhibit linear behavior, converging towards 1 and indicating improved compatibility, potentially leading to reduced thermal hysteresis effects at lower temperatures. These findings offer insights into magneto-structural transitions and hysteresis behaviors, informing the development of high-performance magnetocaloric materials.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121241"},"PeriodicalIF":8.3,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144252746","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":"Roles of Fe and Cu migrations in oxidation mechanisms and magnetic loss of 2:17-type Sm-Co-Fe-Cu-Zr permanent magnets","authors":"Kangjie Chai,&nbsp;Yong Zhang,&nbsp;Wei Zhang,&nbsp;Qiankun Yang,&nbsp;Weisong Wu,&nbsp;Lijiang Ye,&nbsp;Dingshun Yan,&nbsp;Zhiming Li","doi":"10.1016/j.actamat.2025.121237","DOIUrl":"10.1016/j.actamat.2025.121237","url":null,"abstract":"<div><div>Oxidation induced irredeemable magnetic loss is a critical concern in Sm₂Co₁₇-type permanent magnets. Herein, the oxidation mechanisms and the associated magnetic losses of two representative magnets, i.e., a high-energy product grade magnet with relatively high Fe and low Cu contents (service temperature &lt; 350 °C, termed as HE-grade) and a high-temperature grade magnet with low Fe and high Cu contents (service temperature &lt;500 °C, HT-grade), are systematically unraveled. In early oxidation stage-Ⅰ (&lt; 60 h), the HT-grade magnet shows more intense migrations of Cu and Fe, leading to more significant preferential oxidation behavior along 1:5H boundaries and hence higher magnetic losses, as compared to that in the HE-grade counterpart. In oxidation stage-Ⅱ (&gt; 60 h), the diffusions of Fe and Cu atoms in HT-magnet effectively increase the oxygen potential energy of 2:17R cells and hence improve the oxidation resistance, retarding the oxidation process of the bulk magnet. Comparing with the HE-grade magnet oxidized by concurrent decomposition of 1:3R, 1:5H and 2:17R phases, the HT-grade one exhibits the preferential oxidation with more complete cellular structure and lower magnetic loss even under oxidation for 1000 h. Our work presents deep insights into the composition-dependent oxidation of Sm₂Co₁₇-type magnets, which maybe valuable in designing high-performance oxidation-resistant magnets.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121237"},"PeriodicalIF":8.3,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144252554","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":"Simultaneous achievement of large anomalous Nernst effect and reduced thermal conductivity in sintered polycrystalline topological Heusler ferromagnets","authors":"Koichi Oyanagi ,&nbsp;Hossein Sepehri-Amin ,&nbsp;Kenta Takamori ,&nbsp;Terumasa Tadano ,&nbsp;Takumi Imamura ,&nbsp;Ren Nagasawa ,&nbsp;Krishnan Mahalingam ,&nbsp;Takamasa Hirai ,&nbsp;Fuyuki Ando ,&nbsp;Yuya Sakuraba ,&nbsp;Satoru Kobayashi ,&nbsp;Ken-ichi Uchida","doi":"10.1016/j.actamat.2025.121239","DOIUrl":"10.1016/j.actamat.2025.121239","url":null,"abstract":"<div><div>Thermoelectric conversion based on the anomalous Nernst effect (ANE) is promising for energy harvesting as its transverse geometry enables the design of large-scale thermoelectric devices with simple structures. While topological ferromagnets, typically single crystals, exhibit large ANE, achieving high conversion performance remains challenging because it also requires high electric conductivity and low thermal conductivity. Here, we report enhanced transverse thermoelectric conversion performance in polycrystalline topological ferromagnet Co₂MnGa (CMG) prepared by spark plasma sintering. Optimization of the sintering conditions for CMG leads to the anomalous Nernst coefficient of 7.5 µV K^-1 at room temperature, comparable to the highest value reported for the single crystals, and simultaneously reduces its thermal conductivity by 34 % compared to that of the single crystals without affecting the electric conductivity. Owing to the transport properties that overcome conventional trade-off relations, our optimized CMG slab shows the record-high value of the dimensionless figure of merit for ANE at room temperature. Detailed nano/microstructure characterizations and first-principles phonon calculations clarify the unconventional dependence of the transport properties on the degree of crystalline ordering and morphology of crystal-domain boundaries. The results reveal the potential of polycrystalline topological materials for transverse thermoelectric applications and suggest alternative strategies to nanostructuring for enhancing thermoelectric performance.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121239"},"PeriodicalIF":8.3,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144238178","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":"Mechanical enhancement of MgO-CaO ceramics through transition interface design: molecular dynamics simulations and experimental validation","authors":"Yunjie Dong ,&nbsp;Zhoufu Wang ,&nbsp;Hao Liu ,&nbsp;Yan Ma ,&nbsp;Chengji Deng ,&nbsp;Zhongfeng Xia ,&nbsp;Zhenghuang Quan ,&nbsp;Xitang Wang ,&nbsp;Ling Zhang","doi":"10.1016/j.actamat.2025.121233","DOIUrl":"10.1016/j.actamat.2025.121233","url":null,"abstract":"<div><div>This study aims at the inadequate mechanical properties of MgO-CaO ceramics used in high-temperature alloy smelting, achieving significant improvements through interface design. Molecular dynamics simulations reveal the microscopic mechanisms underlying the poor mechanical properties of MgO-CaO ceramics. Specifically, the weak bonding strength at the grain boundaries between MgO and CaO results in the MgO-CaO interface acting as a conduit for the rapid propagation of cracks, with minimal effect on crack deflection. To address this issue, the interfacial bond strength was improved by constructing transition layers at the interface using CaLaAlO₄. Molecular dynamics simulations show that CaLaAlO₄ reacts well with MgO and CaO crystals, forming dual-sided transition layers at the MgO-CaO interface. This increases the interfacial binding energy from 1.266 J/m² to 3.369 J/m² and 3.320 J/m². Interfacial tensile simulations also reveal significant improvements in mechanical properties. Furthermore, the incorporation of CaLaAlO₄ suppresses crack propagation rates and induces crack deflection at the MgO-CaO interface. Finally, experimental results confirm the effectiveness of the microstructural design and the enhanced macroscopic performance. At 0.4 mol % CaLaAlO₄, the MgO-CaO ceramics achieved optimal performance, with a flexural strength of 130.92 MPa and specific fracture energy of 2.91 kJ/m². The mechanical strength increased by 3.4 times compared to the pre-introduction period. Microstructural analysis confirmed dual-sided transitional interfaces and showed that the CaLaAlO₄ phase hindered crack propagation. This work establishes fundamental principles for microstructural design of high-performance MgO-CaO ceramics operating under extreme environments, offering theoretical frameworks for interface-controlled refractory material development.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121233"},"PeriodicalIF":8.3,"publicationDate":"2025-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144237440","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":"Temperature and dose effects on dislocation loops in self-ion irradiated high-purity iron","authors":"Yao Li ,&nbsp;Zehui Qi ,&nbsp;Arunodaya Bhattacharya ,&nbsp;Steven J. Zinkle","doi":"10.1016/j.actamat.2025.121235","DOIUrl":"10.1016/j.actamat.2025.121235","url":null,"abstract":"<div><div>Body-centered cubic (BCC) Fe-based alloys are promising candidate materials for advanced nuclear reactors. However, a detailed understanding of irradiation induced dislocation loop microstructure development remains unresolved. It is a widespread belief that 〈001〉 loops become increasingly favorable over ½〈111〉 loops as irradiation temperature rises above ∼300 C. Unfortunately, the temperature effects on 〈001〉 loop have been primarily examined in in-situ irradiation on TEM thin foils but poorly explored on bulk Fe due to exceedingly limited experimental studies on bulk specimens, raising concerns about the potential influence of TEM thin foil artifacts on observed results. In this study, we conducted experiments on ultra-high purity BCC Fe specimens irradiated with 6.7–8 MeV Fe ions over a wide temperature range on bulk samples. We investigated the effects of temperature (T_irr = 250–500 °C), dose rate (10⁻⁵ to 10⁻³ dpa/s), and dose (0.35 to 3.5 dpa) on the formation and evolution of 〈001〉 and ½〈111〉 loops as well as cavity (void) formation. Post-irradiation Burgers vector analysis via <strong>g•b</strong> method on dislocation segments and loops revealed that 〈001〉 loop fraction does not show a monotonic positive correlation with irradiation temperature. Combined with previous and current theoretical as well as experimental findings, we explore the temperature effects on all existing models of 〈001〉 loop formation. We conclude that the prevailing reports regarding the dominance of 〈001〉 loops in Fe at elevated temperatures are mainly attributable to the loss of glissile ½〈111〉 clusters in TEM thin foil experiments.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121235"},"PeriodicalIF":8.3,"publicationDate":"2025-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144238297","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":"Effects of La on the clustering process of B2-NiAl nanoparticles in maraging steels: Atomic-scale characterization and molecular dynamics simulation using deep learning potential","authors":"Haiyan Wang ,&nbsp;Xueyun Gao ,&nbsp;Gang Sha ,&nbsp;Lei Xing ,&nbsp;Wenbo Fan ,&nbsp;Huijie Tan","doi":"10.1016/j.actamat.2025.121234","DOIUrl":"10.1016/j.actamat.2025.121234","url":null,"abstract":"<div><div>Maraging steels strengthened by coherent B2-NiAl precipitates exhibit an exceptional combination of strength and toughness, and trace amounts of rare earth (RE) elements can further enhance their mechanical performance through molten steel purification and microstructure tuning, yet the atomic-scale mechanisms governing RE effects on the NiAl precipitation remain unclear. Here, we unveil how La accelerates NiAl clustering and ordering in Fe-Ni-Al system through a synergistic combination of atomic-scale characterization, and a novel deep learning potential enabling multi-component atomic simulations. Atom probe tomography (APT) and high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) reveal La enhances NiAl cluster density and growth kinetics, yielding earlier peak hardness during aging. Molecular dynamics simulations demonstrate La increases thermodynamic driving forces for precipitation and promotes Ni-Al pair ordering through strong Ni-La atomic interactions, as validated by first-principles binding energy calculations. This work establishes a paradigm integrating machine-learning enhanced atomistic simulations with advanced characterization to decode RE effects in complex alloys, and offers transformative strategies for high-performance alloy development targeting extreme service environments.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121234"},"PeriodicalIF":8.3,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144237509","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":"Strong hydrogen trapping by tangled dislocations in cold-drawn pearlitic steels","authors":"Chao Huang ,&nbsp;Chuanjie Cui ,&nbsp;Ranming Niu ,&nbsp;Fenghua Lu ,&nbsp;Cheng-Yun Wu ,&nbsp;Xiaoxiong Zhu ,&nbsp;Hongzhou Lu ,&nbsp;Yongqing Zhang ,&nbsp;Pang-Yu Liu ,&nbsp;Bosheng Dong ,&nbsp;Yi-Hsuan Sun ,&nbsp;Hongjian Wang ,&nbsp;Wei Li ,&nbsp;Hung-Wei Yen ,&nbsp;Aimin Guo ,&nbsp;Julie M. Cairney ,&nbsp;Emilio Martínez-Pañeda ,&nbsp;Eason Yi-Sheng Chen","doi":"10.1016/j.actamat.2025.121231","DOIUrl":"10.1016/j.actamat.2025.121231","url":null,"abstract":"<div><div>The presence of diffusible hydrogen atoms can lead to hydrogen embrittlement in steels, compromising their structural integrity. A potential solution is incorporating strong hydrogen traps into the microstructures to immobilize hydrogen solute atoms and prevent their diffusion towards stress-prone areas where embrittlement is most likely to occur. However, creating materials with effective hydrogen traps usually involves adding expensive alloying elements, which increase the production costs, hindering the adoption of this strategy in the steel industry. Here we show that cold drawing of pearlitic steel rods introduces a high density of dislocations that accumulate and tangle at cementite-ferrite interfaces; this strengthens the steel and make it less susceptible to embrittlement. We use atom probe tomography to confirm that these tangled dislocations firmly trap hydrogen in a steel that displays low embrittlement susceptibility. Our findings suggest a pathway for producing metallic materials that have an excellent combination of high strength and hydrogen embrittlement resistance, underscoring the potential of using structural defects as cost-effective hydrogen traps.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121231"},"PeriodicalIF":8.3,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144237503","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}