Pub Date : 2025-11-08DOI: 10.1016/j.scriptamat.2025.117087
D. Zöllner , P.R. Rios
Mean-field theories of grain growth have been established for more than 70 years. They rely on the concepts of average grain size and self-similar size and edge distributions. In contrast, mesoscopic computer simulations enable the observation of a large number of grains over long annealing time spans. Thus, they allow the detailed surveillance of the behavior of individual grains. Hence, while the average grain size is an important construct for mean-field theories, using computer simulations we show that individual grains with the same number of edges from one polycrystalline structure evolve by distinct paths. As a result, the self-similar grain size and number of edges distributions form in a complex manner.
{"title":"A new perspective on self-similar grain growth","authors":"D. Zöllner , P.R. Rios","doi":"10.1016/j.scriptamat.2025.117087","DOIUrl":"10.1016/j.scriptamat.2025.117087","url":null,"abstract":"<div><div>Mean-field theories of grain growth have been established for more than 70 years. They rely on the concepts of average grain size and self-similar size and edge distributions. In contrast, mesoscopic computer simulations enable the observation of a large number of grains over long annealing time spans. Thus, they allow the detailed surveillance of the behavior of individual grains. Hence, while the average grain size is an important construct for mean-field theories, using computer simulations we show that individual grains with the same number of edges from one polycrystalline structure evolve by distinct paths. As a result, the self-similar grain size and number of edges distributions form in a complex manner.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"273 ","pages":"Article 117087"},"PeriodicalIF":5.6,"publicationDate":"2025-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145527336","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 : 2025-11-08DOI: 10.1016/j.scriptamat.2025.117084
Tatsuya Ito , Yuhei Ogawa , Wu Gong , Takuro Kawasaki , Akinobu Shibata , Stefanus Harjo
The effect of solute hydrogen on stacking fault evolution in austenitic steels remains debated. In this study, the changes in stacking fault probability in the <111>//loading direction grains family () of hydrogen-charged and non-charged Fe–24Cr–19Ni austenitic steels were evaluated using in situ neutron diffraction during tensile deformation at 223 and 177 K. When values were plotted against macroscopic strain, hydrogen apparently enhanced stacking fault evolution. However, when identical data were translated into the form of versus stress, the superficial hydrogen-effect on notably disappeared. Rather, deformation temperature played more predominant role―lower temperature led to higher regardless of hydrogen-charging, reflecting the reduction of stacking fault energy with decreasing temperature. These findings demonstrate that hydrogen has a minor effect on stacking fault evolution compared with temperature and applied stress.
{"title":"Stress and temperature, rather than hydrogen, govern stacking fault evolution during tensile deformation in Fe–24Cr–19Ni steel","authors":"Tatsuya Ito , Yuhei Ogawa , Wu Gong , Takuro Kawasaki , Akinobu Shibata , Stefanus Harjo","doi":"10.1016/j.scriptamat.2025.117084","DOIUrl":"10.1016/j.scriptamat.2025.117084","url":null,"abstract":"<div><div>The effect of solute hydrogen on stacking fault evolution in austenitic steels remains debated. In this study, the changes in stacking fault probability in the <111>//loading direction grains family (<span><math><msubsup><mi>P</mi><mrow><mtext>SF</mtext></mrow><mn>111</mn></msubsup></math></span>) of hydrogen-charged and non-charged Fe–24Cr–19Ni austenitic steels were evaluated using <em>in situ</em> neutron diffraction during tensile deformation at 223 and 177 K. When <span><math><msubsup><mi>P</mi><mrow><mtext>SF</mtext></mrow><mn>111</mn></msubsup></math></span> values were plotted against macroscopic strain, hydrogen apparently enhanced stacking fault evolution. However, when identical data were translated into the form of <span><math><msubsup><mi>P</mi><mrow><mtext>SF</mtext></mrow><mn>111</mn></msubsup></math></span> versus stress, the superficial hydrogen-effect on <span><math><msubsup><mi>P</mi><mrow><mtext>SF</mtext></mrow><mn>111</mn></msubsup></math></span> notably disappeared. Rather, deformation temperature played more predominant role―lower temperature led to higher <span><math><msubsup><mi>P</mi><mrow><mtext>SF</mtext></mrow><mn>111</mn></msubsup></math></span> regardless of hydrogen-charging, reflecting the reduction of stacking fault energy with decreasing temperature. These findings demonstrate that hydrogen has a minor effect on stacking fault evolution compared with temperature and applied stress.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"273 ","pages":"Article 117084"},"PeriodicalIF":5.6,"publicationDate":"2025-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145527334","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 : 2025-11-07DOI: 10.1016/j.scriptamat.2025.117086
Wei Wu , Junxiao Xu , Fuhua Cao , Yu Zhang , Yiren Wang , Zheng Peng , Yan Chen , Lanhong Dai
Strength and plasticity are critical properties but always unavoidable trade-offs of materials for various service environment. The vast composition-property space of refractory high entropy alloy (RHEAs) enables resolving this trade-off, but makes their composition design highly challenging. Herein, we formulate a physical feature-guided design strategy for RHEAs toward balanced strength-plasticity across strain rates. Three RHEAs with a superior combination of strength and plasticity over wide strain rate ranges were discovered and synthetized. The composition-property diagrams are constructed and an optimal composition range is identified based on model prediction for several typical refractory elements. By decoding the key physical features governing property trade-offs via interpretable machine learning (ML), this study establishes a data-efficient paradigm for multi-objective materials design, demonstrated here for refractory high-entropy alloys but extensible to other complex systems.
{"title":"Physical feature guided design of refractory high entropy alloys for strength-plasticity synergy across wide strain rates","authors":"Wei Wu , Junxiao Xu , Fuhua Cao , Yu Zhang , Yiren Wang , Zheng Peng , Yan Chen , Lanhong Dai","doi":"10.1016/j.scriptamat.2025.117086","DOIUrl":"10.1016/j.scriptamat.2025.117086","url":null,"abstract":"<div><div>Strength and plasticity are critical properties but always unavoidable trade-offs of materials for various service environment. The vast composition-property space of refractory high entropy alloy (RHEAs) enables resolving this trade-off, but makes their composition design highly challenging. Herein, we formulate a physical feature-guided design strategy for RHEAs toward balanced strength-plasticity across strain rates. Three RHEAs with a superior combination of strength and plasticity over wide strain rate ranges were discovered and synthetized. The composition-property diagrams are constructed and an optimal composition range is identified based on model prediction for several typical refractory elements. By decoding the key physical features governing property trade-offs via interpretable machine learning (ML), this study establishes a data-efficient paradigm for multi-objective materials design, demonstrated here for refractory high-entropy alloys but extensible to other complex systems.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"273 ","pages":"Article 117086"},"PeriodicalIF":5.6,"publicationDate":"2025-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145475870","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 : 2025-11-06DOI: 10.1016/j.scriptamat.2025.117053
Moritz Kuglstatter , Nicolas Karpstein , Benjamin Apeleo Zubiri , Mingjian Wu , Jonas Fecher , Erdmann Spiecker , Heinz Werner Höppel , Mathias Göken
Recently, it has been reported that the formation of B2 crystals in CuPdAgRu alloys leads to a notable increase in strength and conductivity. Here, we investigate the microstructural evolution associated with the formation of the ordered B2 phase: Correlative X-ray and electron diffraction analysis confirms the partial transformation of the initial fcc structure of the alloy into B2; the distribution of alloying elements within the latter phase is revealed by atomic-scale energy-dispersive X-ray spectroscopy. 4D-STEM virtual dark-field imaging uncovers a finely and homogeneously distributed B2 phase. High-resolution STEM imaging directly reveals few-nanometer thin plate-like regions of fcc remaining embedded coherently in the B2 matrix with a specific orientation relationship; these regions correlate with an enrichment of Ag and depletion of Cu, contributing to the large lattice misfit between both phases. These observations provide insights into microscopic-level structural changes and their possible influence on macroscopic properties of advanced functional alloys.
{"title":"Microstructural evolution and B2 ordering in a new CuPdAgRu alloy","authors":"Moritz Kuglstatter , Nicolas Karpstein , Benjamin Apeleo Zubiri , Mingjian Wu , Jonas Fecher , Erdmann Spiecker , Heinz Werner Höppel , Mathias Göken","doi":"10.1016/j.scriptamat.2025.117053","DOIUrl":"10.1016/j.scriptamat.2025.117053","url":null,"abstract":"<div><div>Recently, it has been reported that the formation of B2 crystals in CuPdAgRu alloys leads to a notable increase in strength and conductivity. Here, we investigate the microstructural evolution associated with the formation of the ordered B2 phase: Correlative X-ray and electron diffraction analysis confirms the partial transformation of the initial fcc structure of the alloy into B2; the distribution of alloying elements within the latter phase is revealed by atomic-scale energy-dispersive X-ray spectroscopy. 4D-STEM virtual dark-field imaging uncovers a finely and homogeneously distributed B2 phase. High-resolution STEM imaging directly reveals few-nanometer thin plate-like regions of fcc remaining embedded coherently in the B2 matrix with a specific orientation relationship; these regions correlate with an enrichment of Ag and depletion of Cu, contributing to the large lattice misfit between both phases. These observations provide insights into microscopic-level structural changes and their possible influence on macroscopic properties of advanced functional alloys.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"272 ","pages":"Article 117053"},"PeriodicalIF":5.6,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145474574","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 : 2025-11-06DOI: 10.1016/j.scriptamat.2025.117080
Muchun Hou , Fan Lu , Longfei Li , Song Lu , Siliang He , Dong Wang , Jian Zhang , Qiang Feng
This study investigated the microstructural stability of a high-Cr Ni-based single crystal (SX) superalloy without Re addition (0Re13Cr) during long-term (>10,000 h) thermal exposure at 900 °C, in comparison with two SX superalloys containing lower Cr content without/with Re addition (0Re10Cr and 2Re10Cr, respectively). The results show that alloy 0Re13Cr has a lower γ' coarsening rate than alloy 2Re10Cr, while alloy 0Re10Cr has the highest γ' coarsening rate. This highlights the role of Re and Cr in precipitate stabilization. Atom probe tomography analysis indicates the lowest coarsening rate of γ' precipitates in alloy 0Re13Cr can be ascribed to the higher level of Cr enrichment in the γ matrix, which significantly decreases effective diffusion rate and γ/γ' interfacial energy. These findings suggest that increasing the enrichment of Cr in the γ matrix without triggering topologically close-packed phase precipitation can help develop cost-effective Ni-based SX alloys for industrial gas turbine applications.
{"title":"Effect of high-Cr content on the coarsening behavior of γ' precipitates in Ni-based single crystal superalloys: A comparative study with rhenium-containing superalloys","authors":"Muchun Hou , Fan Lu , Longfei Li , Song Lu , Siliang He , Dong Wang , Jian Zhang , Qiang Feng","doi":"10.1016/j.scriptamat.2025.117080","DOIUrl":"10.1016/j.scriptamat.2025.117080","url":null,"abstract":"<div><div>This study investigated the microstructural stability of a high-Cr Ni-based single crystal (SX) superalloy without Re addition (0Re13Cr) during long-term (>10,000 h) thermal exposure at 900 °C, in comparison with two SX superalloys containing lower Cr content without/with Re addition (0Re10Cr and 2Re10Cr, respectively). The results show that alloy 0Re13Cr has a lower γ' coarsening rate than alloy 2Re10Cr, while alloy 0Re10Cr has the highest γ' coarsening rate. This highlights the role of Re and Cr in precipitate stabilization. Atom probe tomography analysis indicates the lowest coarsening rate of γ' precipitates in alloy 0Re13Cr can be ascribed to the higher level of Cr enrichment in the γ matrix, which significantly decreases effective diffusion rate and γ/γ' interfacial energy. These findings suggest that increasing the enrichment of Cr in the γ matrix without triggering topologically close-packed phase precipitation can help develop cost-effective Ni-based SX alloys for industrial gas turbine applications.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"272 ","pages":"Article 117080"},"PeriodicalIF":5.6,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145474575","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 : 2025-11-06DOI: 10.1016/j.scriptamat.2025.117085
Jianlin Lu, Rongtian Cao, Zhongsheng Yang, Zhijun Wang, Junjie Li, Jincheng Wang, Lei Wang, Feng He
Aluminum (Al) and titanium (Ti) are widely used for L12 precipitation, whereas niobium (Nb) promotes D022 precipitates formation. However, to regulate L12-D022 dual superlattices, Al and Ti are typically co-regulated as a compositional module in conjunction with Nb additions, which neglects their individual effects on precipitation behaviors. Our study systematically investigates the distinct effects of Al and Ti on L12-D022 dual superlattices formation through controlled individual additions in a Ni2.1CoCrFeNb0.2 high entropy alloy (HEA). At 0.5 at.% Al, L12 superlattice nucleates at D022/matrix interfaces, forming D022-L12 siamese-twin precipitates, while 1 at.% Al produces exclusive L12 precipitates. Conversely, Ti (1–2 at.%) yields isolated L12 precipitates within matrix with dominant D022 precipitates. These results demonstrate that Al drives D022 to L12 transformation whereas Ti maintains D022 stability while allowing discrete L12 formation. The HEA strengthened by siamese-twin precipitates achieves a balance strength and elongation, offering a design strategy for dual-superlattice strengthened HEAs.
{"title":"Opposite effects of Al and Ti on the precipitation behaviors of D022-L12 dual superlattices in high entropy alloys","authors":"Jianlin Lu, Rongtian Cao, Zhongsheng Yang, Zhijun Wang, Junjie Li, Jincheng Wang, Lei Wang, Feng He","doi":"10.1016/j.scriptamat.2025.117085","DOIUrl":"10.1016/j.scriptamat.2025.117085","url":null,"abstract":"<div><div>Aluminum (Al) and titanium (Ti) are widely used for L1<sub>2</sub> precipitation, whereas niobium (Nb) promotes D0<sub>22</sub> precipitates formation. However, to regulate L1<sub>2</sub>-D0<sub>22</sub> dual superlattices, Al and Ti are typically co-regulated as a compositional module in conjunction with Nb additions, which neglects their individual effects on precipitation behaviors. Our study systematically investigates the distinct effects of Al and Ti on L1<sub>2</sub>-D0<sub>22</sub> dual superlattices formation through controlled individual additions in a Ni<sub>2.1</sub>CoCrFeNb<sub>0.2</sub> high entropy alloy (HEA). At 0.5 at.% Al, L1<sub>2</sub> superlattice nucleates at D0<sub>22</sub>/matrix interfaces, forming D0<sub>22</sub>-L1<sub>2</sub> siamese-twin precipitates, while 1 at.% Al produces exclusive L1<sub>2</sub> precipitates. Conversely, Ti (1–2 at.%) yields isolated L1<sub>2</sub> precipitates within matrix with dominant D0<sub>22</sub> precipitates. These results demonstrate that Al drives D0<sub>22</sub> to L1<sub>2</sub> transformation whereas Ti maintains D0<sub>22</sub> stability while allowing discrete L1<sub>2</sub> formation. The HEA strengthened by siamese-twin precipitates achieves a balance strength and elongation, offering a design strategy for dual-superlattice strengthened HEAs.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"272 ","pages":"Article 117085"},"PeriodicalIF":5.6,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145474571","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 : 2025-11-06DOI: 10.1016/j.scriptamat.2025.117081
Muyuan Li , Xuejian Li , Hailong Shi , Fanghan Chi , Xiaoshi Hu , Chao Xu , Bo Guan , Wenke Wang , Xiaojun Wang
The intragranular dispersion strategy of particles in solidification can enhance the mechanical properties of metal matrix composites (MMCs). However, it is extremely challenging for particles to be captured by the solid-liquid interface and dispersed within grains during solidification. In this work, a strategy to modulate the viscous drag force acting on particles was proposed to achieve intragranular dispersion in graphene (Gr) reinforced magnesium matrix composites. Gr decorated with MgOnp was successfully synthesized and uniformly dispersed in Mg matrix through in-situ reactions. The incorporation of Gr within grains is attributed to the viscous drag force overcoming the pushing force exerted by solid-liquid interface. The yield strength, ultimate tensile strength and elongation of intragranular-dispersed Gr/Mg are enhanced by 154 %, 331 % and 200 % compared to intergranular-aggregated Gr/Mg, demonstrating an excellent strength-ductility synergy. This work presents an innovative strategy with substantial implications for both theoretical and processing optimization of as-cast MMCs.
{"title":"Overcoming the strength-ductility trade-off in magnesium matrix composites via an intragranular dispersion strategy","authors":"Muyuan Li , Xuejian Li , Hailong Shi , Fanghan Chi , Xiaoshi Hu , Chao Xu , Bo Guan , Wenke Wang , Xiaojun Wang","doi":"10.1016/j.scriptamat.2025.117081","DOIUrl":"10.1016/j.scriptamat.2025.117081","url":null,"abstract":"<div><div>The intragranular dispersion strategy of particles in solidification can enhance the mechanical properties of metal matrix composites (MMCs). However, it is extremely challenging for particles to be captured by the solid-liquid interface and dispersed within grains during solidification. In this work, a strategy to modulate the viscous drag force acting on particles was proposed to achieve intragranular dispersion in graphene (Gr) reinforced magnesium matrix composites. Gr decorated with MgO<sub>np</sub> was successfully synthesized and uniformly dispersed in Mg matrix through <em>in-situ</em> reactions. The incorporation of Gr within grains is attributed to the viscous drag force overcoming the pushing force exerted by solid-liquid interface. The yield strength, ultimate tensile strength and elongation of intragranular-dispersed Gr/Mg are enhanced by 154 %, 331 % and 200 % compared to intergranular-aggregated Gr/Mg, demonstrating an excellent strength-ductility synergy. This work presents an innovative strategy with substantial implications for both theoretical and processing optimization of as-cast MMCs.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":"272 ","pages":"Article 117081"},"PeriodicalIF":5.6,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145474570","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