Pub Date : 2026-03-01Epub Date: 2026-01-31DOI: 10.1016/j.msea.2026.149862
Min Young Sung , Tae Jin Jang , Hahun Lee , Gunjick Lee , Seungjin Nam , Gyumin Park , Siyuan Zhang , Se-Ho Kim , Seok Su Sohn
Achieving a favorable balance of strength and ductility at cryogenic temperatures requires concurrent control of yield strength and deformation mechanisms. Conventional carbide-based strengthening in Fe-based alloys can improve strength and modify deformation behavior, but often induces strain localization due to the non-shearable nature of carbides. Here, we show that nanoscale Cu precipitation in a designed Fe66Cr14Ni12Mn2Mo1Cu5 alloy simultaneously enhances strength and tailors stacking-fault energy (SFE) to activate multiple deformation modes. The coherent Cu precipitates with an average radius of ∼3 nm and a volume fraction of ∼5% contribute ∼190 MPa to yield strength through a shearing mechanism. The depletion of matrix Cu reduces the SFE from 23.3 mJ m−2 in the solutionized alloy to 15.6 mJ m−2, enabling deformation twinning at ambient temperature and promoting an earlier onset of γ→α′ martensitic transformation at 77 K. Consequently, the present alloy achieves a tensile strength of 1.43 GPa with ∼70% elongation at 77 K, corresponding to a strength–ductility product exceeding 10 GPa%. These findings establish precipitation engineering with shearable Cu precipitates as an effective strategy for simultaneously enhancing strength and controlling deformation pathways in cryogenic structural alloys.
{"title":"Strength–ductility synergy at ambient and cryogenic temperatures via Cu-precipitation-tuned stacking fault energy in a Fe–Cr–Ni–Mn–Mo–Cu alloy","authors":"Min Young Sung , Tae Jin Jang , Hahun Lee , Gunjick Lee , Seungjin Nam , Gyumin Park , Siyuan Zhang , Se-Ho Kim , Seok Su Sohn","doi":"10.1016/j.msea.2026.149862","DOIUrl":"10.1016/j.msea.2026.149862","url":null,"abstract":"<div><div>Achieving a favorable balance of strength and ductility at cryogenic temperatures requires concurrent control of yield strength and deformation mechanisms. Conventional carbide-based strengthening in Fe-based alloys can improve strength and modify deformation behavior, but often induces strain localization due to the non-shearable nature of carbides. Here, we show that nanoscale Cu precipitation in a designed Fe<sub>66</sub>Cr<sub>14</sub>Ni<sub>12</sub>Mn<sub>2</sub>Mo<sub>1</sub>Cu<sub>5</sub> alloy simultaneously enhances strength and tailors stacking-fault energy (SFE) to activate multiple deformation modes. The coherent Cu precipitates with an average radius of ∼3 nm and a volume fraction of ∼5% contribute ∼190 MPa to yield strength through a shearing mechanism. The depletion of matrix Cu reduces the SFE from 23.3 mJ m<sup>−2</sup> in the solutionized alloy to 15.6 mJ m<sup>−2</sup>, enabling deformation twinning at ambient temperature and promoting an earlier onset of γ→α′ martensitic transformation at 77 K. Consequently, the present alloy achieves a tensile strength of 1.43 GPa with ∼70% elongation at 77 K, corresponding to a strength–ductility product exceeding 10 GPa%. These findings establish precipitation engineering with shearable Cu precipitates as an effective strategy for simultaneously enhancing strength and controlling deformation pathways in cryogenic structural alloys.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"955 ","pages":"Article 149862"},"PeriodicalIF":7.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-01Epub Date: 2026-02-03DOI: 10.1016/j.msea.2026.149886
Zhiyu Gao , Qiangqiang Li , Zexi Long , Yongsheng Miao , Da Xu , Gaosong Wang , Zhihao Zhao
We investigate the evolution of microstructure and mechanical properties in Al-Cu-Mg-Ag alloy wires following pre-deformation using a novel large-strain cold rolling process. The cold-rolling pre-deformation significantly enhances strength while maintaining good ductility. Under conventional peak-aged conditions, the wire exhibits tensile strength, yield strength, and elongation values of 479 MPa, 420 MPa, and 13.6%, respectively. In contrast, after 69% pre-deformation followed by peak aging at 180 °C, the ultimate tensile strength and yield strength increase to 573 MPa and 547 MPa, respectively, while elongation remains at 10.8%. Severe pre-deformation (>50%) introduces a high density of dislocations and vacancies into the alloy wires, accelerating the age-hardening kinetics. Quantitative analysis reveals a significant increase in the number density of both θ′ and Ω precipitates. Rather than suppressing Ω precipitation, severe pre-deformation promotes its nucleation, resulting in a markedly higher volume fraction and number density of the Ω phase. Even after over-aging, a substantial volume fraction of the Ω phase remains present, although reduced relative to the peak-aged condition. Moreover, increasing pre-deformation significantly reduces the width of precipitate-free zones (PFZs). Quantitative strength analysis of peak-aged wires processed via different routes indicates that the enhancement in mechanical properties is mainly due to dislocation strengthening and grain refinement, while pre-deformation does not improve precipitation strengthening.
{"title":"Effect of severe cold rolling and aging on the microstructure and mechanical properties of an Al-Cu-Mg-Ag alloy wire","authors":"Zhiyu Gao , Qiangqiang Li , Zexi Long , Yongsheng Miao , Da Xu , Gaosong Wang , Zhihao Zhao","doi":"10.1016/j.msea.2026.149886","DOIUrl":"10.1016/j.msea.2026.149886","url":null,"abstract":"<div><div>We investigate the evolution of microstructure and mechanical properties in Al-Cu-Mg-Ag alloy wires following pre-deformation using a novel large-strain cold rolling process. The cold-rolling pre-deformation significantly enhances strength while maintaining good ductility. Under conventional peak-aged conditions, the wire exhibits tensile strength, yield strength, and elongation values of 479 MPa, 420 MPa, and 13.6%, respectively. In contrast, after 69% pre-deformation followed by peak aging at 180 °C, the ultimate tensile strength and yield strength increase to 573 MPa and 547 MPa, respectively, while elongation remains at 10.8%. Severe pre-deformation (>50%) introduces a high density of dislocations and vacancies into the alloy wires, accelerating the age-hardening kinetics. Quantitative analysis reveals a significant increase in the number density of both θ′ and Ω precipitates. Rather than suppressing Ω precipitation, severe pre-deformation promotes its nucleation, resulting in a markedly higher volume fraction and number density of the Ω phase. Even after over-aging, a substantial volume fraction of the Ω phase remains present, although reduced relative to the peak-aged condition. Moreover, increasing pre-deformation significantly reduces the width of precipitate-free zones (PFZs). Quantitative strength analysis of peak-aged wires processed via different routes indicates that the enhancement in mechanical properties is mainly due to dislocation strengthening and grain refinement, while pre-deformation does not improve precipitation strengthening.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"955 ","pages":"Article 149886"},"PeriodicalIF":7.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-01Epub Date: 2026-02-02DOI: 10.1016/j.msea.2026.149873
Yuanchen Liang , Yang Liu , Yufeng Liu , Lin Zhang , Peng Zhang , Sha Zhang , Na Liu , Zhou Li , Xuanhui Qu
Increasing the proportion of recycled alloy is significant for preparing low-cost powder metallurgy (PM) Ni-based superalloys. However, as this proportion rises, the oxygen content in superalloy powders prepared by gas atomization increases, degrading the mechanical properties of PM superalloys. Therefore, this study investigated the influence of oxygen content on the microstructure, creep performance, and failure mechanism of HIF state FGH96 superalloys. Results reveal that during HIF, the strain induced boundary migration mechanism leads to substantial SGs formation at Prior particle boundaries (PPBs) in the HIP state alloy, with strain gradients driving recrystallization inward from PPBs into powder interior. High-oxygen superalloys exhibit a small grains (SGs) fraction of 52%, compared to 37% in low-oxygen superalloys. During creep, the abundant grain boundaries (GBs) in SGs regions hinder dislocation motion, leading to more severe low angle grain boundaries proliferation than in coarse grains. This results in stress concentration and crack propagation within SGs regions. Consequently, high-oxygen superalloys experience more pronounced stress concentration in SGs, leading to a faster steady-state creep rate of 3.31×10−2 h−1 with a shorter creep life of 52 h, compared to 85 h for low-oxygen superalloys. First-principles calculations show that pore nucleation preferentially occurs at the high energy MC-γ′ interface, followed by the γ-γ′ phase interface, and lastly at the γ-γ grain boundary. Finite element simulations confirm that the abundant GBs in SGs regions intensify GBs sliding, causing stress accumulation and facilitating crack propagation during high-temperature deformation. Based on these results, by increasing the hot-deformation temperature to suppress recrystallization, the SGs fraction in high-oxygen superalloys was optimized to 38.7% and the creep life is improved to 84 h, which is close to that of low-oxygen superalloys. This study offers technical support for microstructure control and performance optimization of low-cost PM Ni-based superalloys.
{"title":"Tailoring secondary grains via recrystallization control to restore creep life in high-oxygen PM superalloys","authors":"Yuanchen Liang , Yang Liu , Yufeng Liu , Lin Zhang , Peng Zhang , Sha Zhang , Na Liu , Zhou Li , Xuanhui Qu","doi":"10.1016/j.msea.2026.149873","DOIUrl":"10.1016/j.msea.2026.149873","url":null,"abstract":"<div><div>Increasing the proportion of recycled alloy is significant for preparing low-cost powder metallurgy (PM) Ni-based superalloys. However, as this proportion rises, the oxygen content in superalloy powders prepared by gas atomization increases, degrading the mechanical properties of PM superalloys. Therefore, this study investigated the influence of oxygen content on the microstructure, creep performance, and failure mechanism of HIF state FGH96 superalloys. Results reveal that during HIF, the strain induced boundary migration mechanism leads to substantial SGs formation at Prior particle boundaries (PPBs) in the HIP state alloy, with strain gradients driving recrystallization inward from PPBs into powder interior. High-oxygen superalloys exhibit a small grains (SGs) fraction of 52%, compared to 37% in low-oxygen superalloys. During creep, the abundant grain boundaries (GBs) in SGs regions hinder dislocation motion, leading to more severe low angle grain boundaries proliferation than in coarse grains. This results in stress concentration and crack propagation within SGs regions. Consequently, high-oxygen superalloys experience more pronounced stress concentration in SGs, leading to a faster steady-state creep rate of 3.31×10<sup>−2</sup> h<sup>−1</sup> with a shorter creep life of 52 h, compared to 85 h for low-oxygen superalloys. First-principles calculations show that pore nucleation preferentially occurs at the high energy MC-γ′ interface, followed by the γ-γ′ phase interface, and lastly at the γ-γ grain boundary. Finite element simulations confirm that the abundant GBs in SGs regions intensify GBs sliding, causing stress accumulation and facilitating crack propagation during high-temperature deformation. Based on these results, by increasing the hot-deformation temperature to suppress recrystallization, the SGs fraction in high-oxygen superalloys was optimized to 38.7% and the creep life is improved to 84 h, which is close to that of low-oxygen superalloys. This study offers technical support for microstructure control and performance optimization of low-cost PM Ni-based superalloys.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"956 ","pages":"Article 149873"},"PeriodicalIF":7.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146147406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2026-01-06DOI: 10.1016/j.msea.2026.149743
Pengpeng Huang, Yizhe Meng, Yake Wu, Feng Jiang, Jun Sun
SiCp-reinforced aluminum matrix composites (AMCs) are promising lightweight structural materials owing to high specific strength, high specific modulus, and excellent wear resistance. However, their application is severely limited by the poor plasticity, which originates mainly from the formation of interfacial brittle Al4C3 and strain incompatibility between the SiC phase and the matrix. Here, we present a novel strategy for tailoring the SiC/Al interface structure in the SiCp/Al-Cu-Mg composites by integrating low-temperature sintering (566 °C) with closed-die hot forging. The designed strategy not only suppresses the formation of Al4C3, but also preserves local porosity adjacent to the SiC particles, enabling the formation of low-strain zones (LSZs) there during subsequent hot forging. As a result, the composites with 5, 10, and 15 wt % SiC all exhibit favorable strength-ductility synergy, where the 5 wt% SiCp/Al-Cu-Mg composite shows a yield strength of 332.0 MPa, an ultimate tensile strength of 458.0 MPa and an elongation of 11.0 %. Without forming the brittle Al4C3 phase, the LSZs further serve to redistribute dislocations, mitigate strain localization and provide more dislocation storage space in the SiC/Al interface zones, thereby alleviating strain incompatibility and reducing stress concentration towards simultaneous property enhancement over the unreinforced alloy. Our work offers an innovative feasible strategy for making high-performance AMCs by tailoring the interfacial structure.
sicp增强铝基复合材料（AMCs）具有高比强度、高比模量和优异的耐磨性，是一种很有前途的轻量化结构材料。然而，塑性差严重限制了它们的应用，这主要源于界面脆性Al4C3的形成以及SiC相与基体之间的应变不相容。在这里，我们提出了一种将低温烧结（566°C）与闭模热锻相结合的方法来定制SiCp/Al- cu - mg复合材料中SiC/Al界面结构的新策略。设计的策略不仅抑制了Al4C3的形成，而且保留了SiC颗粒附近的局部孔隙，从而在随后的热锻过程中形成了低应变区（LSZs）。结果表明，添加5%、10%和15% SiC的复合材料均表现出良好的强度-塑性协同效应，其中5% SiCp/Al-Cu-Mg复合材料的屈服强度为332.0 MPa，极限抗拉强度为458.0 MPa，伸长率为11.0%。在不形成脆性Al4C3相的情况下，LSZs进一步重新分配位错，减轻应变局部化，并在SiC/Al界面区提供更多的位错存储空间，从而减轻应变不相容，减少应力集中，同时提高合金的性能。我们的工作提供了一种创新的可行策略，通过定制界面结构来制造高性能的amc。
{"title":"Achieving strength-ductility synergy in SiCp/Al-Cu-Mg composites via deploying low-strain zones around Al4C3-free interfaces","authors":"Pengpeng Huang, Yizhe Meng, Yake Wu, Feng Jiang, Jun Sun","doi":"10.1016/j.msea.2026.149743","DOIUrl":"10.1016/j.msea.2026.149743","url":null,"abstract":"<div><div>SiC<sub>p</sub>-reinforced aluminum matrix composites (AMCs) are promising lightweight structural materials owing to high specific strength, high specific modulus, and excellent wear resistance. However, their application is severely limited by the poor plasticity, which originates mainly from the formation of interfacial brittle Al<sub>4</sub>C<sub>3</sub> and strain incompatibility between the SiC phase and the matrix. Here, we present a novel strategy for tailoring the SiC/Al interface structure in the SiC<sub>p</sub>/Al-Cu-Mg composites by integrating low-temperature sintering (566 °C) with closed-die hot forging. The designed strategy not only suppresses the formation of Al<sub>4</sub>C<sub>3</sub>, but also preserves local porosity adjacent to the SiC particles, enabling the formation of low-strain zones (LSZs) there during subsequent hot forging. As a result, the composites with 5, 10, and 15 wt % SiC all exhibit favorable strength-ductility synergy, where the 5 wt% SiC<sub>p</sub>/Al-Cu-Mg composite shows a yield strength of 332.0 MPa, an ultimate tensile strength of 458.0 MPa and an elongation of 11.0 %. Without forming the brittle Al<sub>4</sub>C<sub>3</sub> phase, the LSZs further serve to redistribute dislocations, mitigate strain localization and provide more dislocation storage space in the SiC/Al interface zones, thereby alleviating strain incompatibility and reducing stress concentration towards simultaneous property enhancement over the unreinforced alloy. Our work offers an innovative feasible strategy for making high-performance AMCs by tailoring the interfacial structure.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"953 ","pages":"Article 149743"},"PeriodicalIF":7.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145922496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2026-01-28DOI: 10.1016/j.msea.2026.149858
Jun Li , Lingying Ye , Yu Wang , Yuhui Wang , Guotong Zou , Tao Duan , Jianguo Tang
Traditional approaches to designing process parameters for new alloys often rely on inefficient trial-and-error methods. In this study, elemental physicochemical parameters were integrated with feature selection to develop a machine learning prediction model with robust predictive capability. Through Pareto analysis, the optimal extrusion parameters for high-strength Al-Mg-Si alloys were determined as an extrusion ratio (EXR) of 40, temperature (EXT) of 540 °C, and speed (EXS) of 1.1 mm/s. Under these conditions, the ultimate tensile strength (UTS), yield strength (YS), and elongation (EL) were 402.4 MPa, 385.5 MPa, and 10.3 %, respectively. Additionally, significant nonlinear interactions between process parameters and mechanical properties were revealed through Shapley additive explanations (SHAP) analysis. Through electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM), the strength-ductility mechanism was attributed to the competing effects of grain boundaries, dislocations, textures, and precipitates. This data-driven strategy provides a robust methodology for optimizing and designing alloy processing parameters.
{"title":"Investigating the effects of extrusion temperature and speed on the mechanical properties of high-strength Al-Mg-Si alloys using machine learning methods","authors":"Jun Li , Lingying Ye , Yu Wang , Yuhui Wang , Guotong Zou , Tao Duan , Jianguo Tang","doi":"10.1016/j.msea.2026.149858","DOIUrl":"10.1016/j.msea.2026.149858","url":null,"abstract":"<div><div>Traditional approaches to designing process parameters for new alloys often rely on inefficient trial-and-error methods. In this study, elemental physicochemical parameters were integrated with feature selection to develop a machine learning prediction model with robust predictive capability. Through Pareto analysis, the optimal extrusion parameters for high-strength Al-Mg-Si alloys were determined as an extrusion ratio (EXR) of 40, temperature (EXT) of 540 °C, and speed (EXS) of 1.1 mm/s. Under these conditions, the ultimate tensile strength (UTS), yield strength (YS), and elongation (EL) were 402.4 MPa, 385.5 MPa, and 10.3 %, respectively. Additionally, significant nonlinear interactions between process parameters and mechanical properties were revealed through Shapley additive explanations (SHAP) analysis. Through electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM), the strength-ductility mechanism was attributed to the competing effects of grain boundaries, dislocations, textures, and precipitates. This data-driven strategy provides a robust methodology for optimizing and designing alloy processing parameters.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"954 ","pages":"Article 149858"},"PeriodicalIF":7.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146075511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2026-01-26DOI: 10.1016/j.msea.2026.149829
Yuheng Zhang , Shuaicheng Zhu , Yihuan Cao , Wei Yong , Hongtao Zhang , Huadong Fu , Jianxin Xie
The development of next-generation aero-engines necessitates wrought superalloys with operational stability at ≥750 °C while maintaining an optimal balance between elevated tensile strength, retained ductility, and hot workability compatible with industrial manufacturing requirements. Accordingly, a Ni-Co based superalloy with the composition of Ni-22Co-12.5Cr-2.9Al-5.5Ti-1.6W-2.4Mo-0.02C-0.02B-0.03Zr (wt%) was designed via integrated high-throughput thermodynamic calculations and machine learning. Post solution treatment and aging, the experimental alloy achieves a γ′ phase volume fraction of ∼45 % with an average radius of ∼92 nm, demonstrating excellent microstructural stability characterized by absent Topologically Close-Packed (TCP) phase formation during 750 °C/500h thermal exposure, alongside a favorable thermal processing window spanning approximately 180 °C. Notably, 1 wt% Ta addition simultaneously enhances yield strength and elongation without inducing deleterious TCP phases, while effectively retarding γ′ coarsening kinetics. Conversely, 1 wt% Nb incorporation improves strength at the expense of severe ductility reduction and accelerated coarsening. The optimized Ta-modified alloy (Ni-Co-1Ta) demonstrates a 15.2 % higher 750 °C yield strength with concurrent ductility improvement relative to TMW-4M3, establishing it as a promising candidate material for next-generation turbine disk applications requiring 750 °C service capability.
{"title":"Composition design and optimization of a Ni-Co based wrought superalloy for 750 °C service","authors":"Yuheng Zhang , Shuaicheng Zhu , Yihuan Cao , Wei Yong , Hongtao Zhang , Huadong Fu , Jianxin Xie","doi":"10.1016/j.msea.2026.149829","DOIUrl":"10.1016/j.msea.2026.149829","url":null,"abstract":"<div><div>The development of next-generation aero-engines necessitates wrought superalloys with operational stability at ≥750 °C while maintaining an optimal balance between elevated tensile strength, retained ductility, and hot workability compatible with industrial manufacturing requirements. Accordingly, a Ni-Co based superalloy with the composition of Ni-22Co-12.5Cr-2.9Al-5.5Ti-1.6W-2.4Mo-0.02C-0.02B-0.03Zr (wt%) was designed via integrated high-throughput thermodynamic calculations and machine learning. Post solution treatment and aging, the experimental alloy achieves a γ′ phase volume fraction of ∼45 % with an average radius of ∼92 nm, demonstrating excellent microstructural stability characterized by absent Topologically Close-Packed (TCP) phase formation during 750 °C/500h thermal exposure, alongside a favorable thermal processing window spanning approximately 180 °C. Notably, 1 wt% Ta addition simultaneously enhances yield strength and elongation without inducing deleterious TCP phases, while effectively retarding γ′ coarsening kinetics. Conversely, 1 wt% Nb incorporation improves strength at the expense of severe ductility reduction and accelerated coarsening. The optimized Ta-modified alloy (Ni-Co-1Ta) demonstrates a 15.2 % higher 750 °C yield strength with concurrent ductility improvement relative to TMW-4M3, establishing it as a promising candidate material for next-generation turbine disk applications requiring 750 °C service capability.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"954 ","pages":"Article 149829"},"PeriodicalIF":7.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146075971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2026-01-26DOI: 10.1016/j.msea.2026.149837
Ba Chen , Abdukadir Amar , Peter K. Liaw , Yiping Lu
A key limitation of TiZrNb-based lightweight refractory medium-entropy alloys (LRMEAs) is their low yield strength, despite their low density and status as the most widely studied system in the family of lightweight refractory alloys. Additive manufacturing (AM) is a technique that builds objects layer by layer, enabling the production of complex metal components with a high degree of design flexibility. In this study, the TiZrNb LRMEA was fabricated by laser melting deposition (LMD) for the first time, and its microstructure and mechanical properties were investigated. The LMD-fabricated TiZrNb LRMEA exhibits a single-phase body-centred-cubic (BCC) structure with an equiaxed grain microstructure, and excellent mechanical properties (with the tensile yield strength of 1185 MPa, a total elongation of 18 % and significant isotropy). This trend represents over a 70 % increase in yield strength compared to its as-cast counterparts, without compromising tensile ductility. The equiaxed grain microstructure is prone to plastic rotational deformation. This feature results in a high density of Geometrically Necessary Dislocations (GNDs), and the accumulation of high-density GNDs increases the strength of the LRMEA. The reduction in the local stress concentration is attributed to the kink bands, which impart the excellent tensile plasticity to the LRMEA. The mechanical properties of the LRMEA are enhanced through multiple mechanisms, including solid-solution strengthening, interstitial-atoms strengthening, and dislocation hardening. The present work provides critical insights into the improvement of mechanical properties in LRMEA using AM, greatly facilitating an understanding of the related mechanisms.
{"title":"Additive manufacturing of TiZrNb lightweight refractory medium-entropy alloy with excellent mechanical properties","authors":"Ba Chen , Abdukadir Amar , Peter K. Liaw , Yiping Lu","doi":"10.1016/j.msea.2026.149837","DOIUrl":"10.1016/j.msea.2026.149837","url":null,"abstract":"<div><div>A key limitation of TiZrNb-based lightweight refractory medium-entropy alloys (LRMEAs) is their low yield strength, despite their low density and status as the most widely studied system in the family of lightweight refractory alloys. Additive manufacturing (AM) is a technique that builds objects layer by layer, enabling the production of complex metal components with a high degree of design flexibility. In this study, the TiZrNb LRMEA was fabricated by laser melting deposition (LMD) for the first time, and its microstructure and mechanical properties were investigated. The LMD-fabricated TiZrNb LRMEA exhibits a single-phase body-centred-cubic (BCC) structure with an equiaxed grain microstructure, and excellent mechanical properties (with the tensile yield strength of 1185 MPa, a total elongation of 18 % and significant isotropy). This trend represents over a 70 % increase in yield strength compared to its as-cast counterparts, without compromising tensile ductility. The equiaxed grain microstructure is prone to plastic rotational deformation. This feature results in a high density of Geometrically Necessary Dislocations (GNDs), and the accumulation of high-density GNDs increases the strength of the LRMEA. The reduction in the local stress concentration is attributed to the kink bands, which impart the excellent tensile plasticity to the LRMEA. The mechanical properties of the LRMEA are enhanced through multiple mechanisms, including solid-solution strengthening, interstitial-atoms strengthening, and dislocation hardening. The present work provides critical insights into the improvement of mechanical properties in LRMEA using AM, greatly facilitating an understanding of the related mechanisms.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"954 ","pages":"Article 149837"},"PeriodicalIF":7.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146076057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2026-01-07DOI: 10.1016/j.msea.2026.149745
Hidetoshi Somekawa , Alok Singh
The dynamic plastic response and deformation behavior at high strain rate regimes is examined on Mg and various dilute binary Mg alloys with fine-grained structure. Nine types of solute atoms (Ag, Al, Ga, In, Li, Mn, Sn, Y and Zn) are selected for alloying in Mg binary alloys with a chemical content of 0.3 at.%. Flow stress and ductility are affected by alloying elements and strain rates. Previous studies have provided that fine-grained Mg and Mg-Mn alloy exhibit huge ductility at low and quasi-static strain rates, attributable to the contribution of grain boundary sliding partially. However, the tensile ductility is determined to be between 5 % and 20 % at present strain rates of 1/s to 1000/s. In addition, regardless of the alloying elements, the strain rate sensitivities at high strain rate regimes are determined to be approximately 0.01–0.05, suggesting dislocation glide as the major deformation mechanism. Microstructural observations reveal <c> and/or <c+a> dislocation slips, as well as basal dislocation slips, instead of deformation twin formations.
{"title":"Tensile response at dynamic strain rates in fine-grained Mg and Mg binary alloys","authors":"Hidetoshi Somekawa , Alok Singh","doi":"10.1016/j.msea.2026.149745","DOIUrl":"10.1016/j.msea.2026.149745","url":null,"abstract":"<div><div>The dynamic plastic response and deformation behavior at high strain rate regimes is examined on Mg and various dilute binary Mg alloys with fine-grained structure. Nine types of solute atoms (Ag, Al, Ga, In, Li, Mn, Sn, Y and Zn) are selected for alloying in Mg binary alloys with a chemical content of 0.3 at.%. Flow stress and ductility are affected by alloying elements and strain rates. Previous studies have provided that fine-grained Mg and Mg-Mn alloy exhibit huge ductility at low and quasi-static strain rates, attributable to the contribution of grain boundary sliding partially. However, the tensile ductility is determined to be between 5 % and 20 % at present strain rates of 1/s to 1000/s. In addition, regardless of the alloying elements, the strain rate sensitivities at high strain rate regimes are determined to be approximately 0.01–0.05, suggesting dislocation glide as the major deformation mechanism. Microstructural observations reveal <c> and/or <c+a> dislocation slips, as well as basal dislocation slips, instead of deformation twin formations.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"953 ","pages":"Article 149745"},"PeriodicalIF":7.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145973516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2026-01-14DOI: 10.1016/j.msea.2026.149788
Xuezhao Wang , Ping Zhang , Xiaomin Jiang , Youqiang Wang
The dynamic deformation behavior and underlying mechanisms of a peak-aged extruded Mg–7.5Gd–3Y–0.5Zr alloy were systematically investigated under combined high-temperature and high–strain-rate conditions. Dynamic compression tests were conducted using a Split Hopkinson Pressure Bar (SHPB) system equipped with a high-temperature device over a wide range of strain rates. Post-impact microstructural evolution was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron backscatter diffraction (EBSD) to establish correlations between mechanical response and temperature-dependent deformation mechanisms.The results demonstrate that the alloy exhibits excellent impact resistance and thermal stability at elevated temperatures, achieving compressive strengths of approximately 664 MPa at 100 °C, 638 MPa at 200 °C, and 619 MPa at 300 °C. At low strain rates, the strengthening behavior is governed by the combined effects of rare-earth hydride particles, age-hardening precipitates, and dynamically formed precipitates, with their relative contributions evolving as temperature increases. In contrast, under high strain rate loading, increasing temperature suppresses dynamic precipitation while promoting twinning, dynamic recrystallization, and adiabatic shear localization. In this regime, thermally stable age-hardening precipitates play a dominant role in maintaining impact strength.The active deformation mechanisms exhibit a clear temperature-dependent transition at high strain rates. Pyramidal slip dominates at 100 °C, while secondary compressive and tensile twinning becomes predominant at 200 °C, accompanied by cooperative activation of multiple slip systems. At 300 °C, basal slip and tensile twinning govern plastic deformation, with pyramidal slip assisting strain accommodation. These transitions reflect enhanced thermal activation of slip and twinning mechanisms at elevated temperatures.Overall, the Mg–7.5Gd–3Y–0.5Zr alloy demonstrates excellent adaptability and stable dynamic mechanical performance under extreme conditions. The synergistic effects of rare-earth strengthening, precipitation behavior, and temperature-dependent deformation mechanisms highlight its strong potential for high-temperature, high–strain-rate lightweight structural applications.
{"title":"Study on the high-temperature dynamic impact mechanical behavior and deformation mechanisms of extruded Mg-Gd alloys","authors":"Xuezhao Wang , Ping Zhang , Xiaomin Jiang , Youqiang Wang","doi":"10.1016/j.msea.2026.149788","DOIUrl":"10.1016/j.msea.2026.149788","url":null,"abstract":"<div><div>The dynamic deformation behavior and underlying mechanisms of a peak-aged extruded Mg–7.5Gd–3Y–0.5Zr alloy were systematically investigated under combined high-temperature and high–strain-rate conditions. Dynamic compression tests were conducted using a Split Hopkinson Pressure Bar (SHPB) system equipped with a high-temperature device over a wide range of strain rates. Post-impact microstructural evolution was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron backscatter diffraction (EBSD) to establish correlations between mechanical response and temperature-dependent deformation mechanisms.The results demonstrate that the alloy exhibits excellent impact resistance and thermal stability at elevated temperatures, achieving compressive strengths of approximately 664 MPa at 100 °C, 638 MPa at 200 °C, and 619 MPa at 300 °C. At low strain rates, the strengthening behavior is governed by the combined effects of rare-earth hydride particles, age-hardening precipitates, and dynamically formed precipitates, with their relative contributions evolving as temperature increases. In contrast, under high strain rate loading, increasing temperature suppresses dynamic precipitation while promoting twinning, dynamic recrystallization, and adiabatic shear localization. In this regime, thermally stable age-hardening precipitates play a dominant role in maintaining impact strength.The active deformation mechanisms exhibit a clear temperature-dependent transition at high strain rates. Pyramidal slip dominates at 100 °C, while secondary compressive and tensile twinning becomes predominant at 200 °C, accompanied by cooperative activation of multiple slip systems. At 300 °C, basal slip and tensile twinning govern plastic deformation, with pyramidal slip assisting strain accommodation. These transitions reflect enhanced thermal activation of slip and twinning mechanisms at elevated temperatures.Overall, the Mg–7.5Gd–3Y–0.5Zr alloy demonstrates excellent adaptability and stable dynamic mechanical performance under extreme conditions. The synergistic effects of rare-earth strengthening, precipitation behavior, and temperature-dependent deformation mechanisms highlight its strong potential for high-temperature, high–strain-rate lightweight structural applications.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"953 ","pages":"Article 149788"},"PeriodicalIF":7.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145973655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study addresses the critical need for localized strengthening of laser direct energy deposited components by developing an innovative induction heat treatment strategy. Focusing on the deposited 18Ni300 layer of a deposit-substrate composite (20Mn2SiCrMo bainitic steel substrate), a short-time (5–30 min) and high-temperature (600 °C) induction heat treatment was proposed to regulate the precipitate evolution and reversed austenite (RA’) formation of 18Ni300 deposits, the synergistic optimization of the strength/toughness was achieved without affecting the 20Mn2SiCrMo substrate’ performance. During heat treatment, the RA’ preferentially nucleates and grows up at the inter-dendritic α′-M laths, intra-dendritic α′-M laths, subgranular boundaries or near the Ni-rich precipitates; meanwhile, the nano-intermetallic compounds, such as η-Ni3Ti, Ni3Mo, and Laves-Fe2Mo, are precipitated sequentially, and the lattice mismatch degree between them and the parent phase increases with the heating time. This multi-scale synergistic evolution mechanism of microstructure enables the 18Ni300 deposit’ yield strength to be increased by 32.8 % under only 10 min of heating, while keeping the decrease in impact toughness within 16.4 %, reaching 1441 MPa and 77.72 J, respectively. Mechanistic analysis shows that the dynamic balance between the lattice mismatch reinforcement and the TRIP effect of RA’ is the key to achieving the strength-toughness synergy. This technology provides a new paradigm for localized control of bimetallic composites, which is of great value in repaired and remanufacturing components serviced in extreme environments, such as rail transportation and ocean engineering.
{"title":"Tailoring nanostructures and mechanical properties of laser direct energy deposited 18Ni300 via induction heat treatment","authors":"Beibei Zhu, Gaofeng Xu, Li Meng, Qianwu Hu, Xu Liu, Xiaoyan Zeng","doi":"10.1016/j.msea.2026.149776","DOIUrl":"10.1016/j.msea.2026.149776","url":null,"abstract":"<div><div>This study addresses the critical need for localized strengthening of laser direct energy deposited components by developing an innovative induction heat treatment strategy. Focusing on the deposited 18Ni300 layer of a deposit-substrate composite (20Mn2SiCrMo bainitic steel substrate), a short-time (5–30 min) and high-temperature (600 °C) induction heat treatment was proposed to regulate the precipitate evolution and reversed austenite (RA’) formation of 18Ni300 deposits, the synergistic optimization of the strength/toughness was achieved without affecting the 20Mn2SiCrMo substrate’ performance. During heat treatment, the RA’ preferentially nucleates and grows up at the inter-dendritic α′-M laths, intra-dendritic α′-M laths, subgranular boundaries or near the Ni-rich precipitates; meanwhile, the nano-intermetallic compounds, such as η-Ni<sub>3</sub>Ti, Ni<sub>3</sub>Mo, and Laves-Fe<sub>2</sub>Mo, are precipitated sequentially, and the lattice mismatch degree between them and the parent phase increases with the heating time. This multi-scale synergistic evolution mechanism of microstructure enables the 18Ni300 deposit’ yield strength to be increased by 32.8 % under only 10 min of heating, while keeping the decrease in impact toughness within 16.4 %, reaching 1441 MPa and 77.72 J, respectively. Mechanistic analysis shows that the dynamic balance between the lattice mismatch reinforcement and the TRIP effect of RA’ is the key to achieving the strength-toughness synergy. This technology provides a new paradigm for localized control of bimetallic composites, which is of great value in repaired and remanufacturing components serviced in extreme environments, such as rail transportation and ocean engineering.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"953 ","pages":"Article 149776"},"PeriodicalIF":7.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145973660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号