Acta Materialia最新文献

{"title":"Synergy Ascension of Piezoresponse and Curie Temperature in Bismuth-layered Ceramics via Defect Engineering","authors":"Weisan Fang, Jie Wu, He Qi, Hang Ma, Donghuan Zhou, Huifen Yu, Zihao Zheng, Jinming Guo, Jun Chen","doi":"10.1016/j.actamat.2025.121108","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121108","url":null,"abstract":"Calcium bismuth niobate (CBN) has emerged as a promising candidate for ultrahigh-temperature piezoelectric applications, exhibiting the highest Curie temperature (<em>T</em>_C) among bismuth layer-structured ferroelectrics (BLSFs). Despite the conventional trade-off between piezoelectric coefficients (<em>d</em>₃₃) and <em>T</em>_C, this study demonstrates a novel 2D defect engineering optimization strategy for CBN ceramics that concurrently achieves a superior <em>d</em>₃₃ (&gt; 20 pC/N) and maintains ultra-high <em>T</em>_C (&gt; 960°C), as well as high electrical resistivity (&gt; 10⁷ Ω·cm at 600°C). Through multi-scale microstructural analysis, optimized in-plane insulating properties and A-site defect orientation distribution promote an increase in spontaneous polarization and the formation of high-density multi-domain states, resulting in excellent electrical performance. Moreover, enhancement of lattice distortions induced by dipoles and the accompanying local electric field improve the stability of the ferroelectric phase and significantly elevate the <em>T</em>_C. This work presents a novel collaborative optimization approach for achieving exceptional overall performance within the Aurivillius compounds in future endeavors.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"55 1","pages":"121108"},"PeriodicalIF":9.4,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143901371","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":"Intermetallic dispersion-strengthened ferritic superalloys with exceptional resistance to radiation-induced hardening","authors":"Kan Ma, Pedro A. Ferreirós, Thomas W. Pfeifer, Robert G. Abernethy, Sophia von Tiedemann, Nianhua Peng, Graeme Greaves, Colin Ophus, Kai Sun, Anamul H Mir, Lumin Wang, Shasha Huang, Shijun Zhao, Patrick E. Hopkins, Christopher D. Hardie, Alexander J. Knowles","doi":"10.1016/j.actamat.2025.121095","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121095","url":null,"abstract":"Intermetallic dispersion-strengthening (IDS) using nano-scale coherent intermetallic precipitates offers a potent strategy to produce high-strength and radiation-resistant steels, whilst addressing the manufacturability challenges of analogous oxide dispersion-strengthened (ODS) steels. However, their performance with intermetallic stability under irradiation damage, such as radiation-induced hardening (RIH), whilst hypothesised, is undemonstrated. Here, we report on a model IDS α(A2) + α’(L2₁) Fe-Ni-Al-Ti ferritic superalloy, which exhibits exceptional resistance to RIH with near-zero hardening after irradiation at 300°C 1 dpa, in contrast to significant RIH in a counterpart coarse precipitate alloy (increase in nano-hardness of 1.0 GPa) and Eurofer97 (0.7 GPa). This irradiation resistance is attributed to the high density of semi-coherent precipitate-matrix interfaces, and partial-disordering L2₁-&gt;B2 which causes a decrease in anti-phase boundary energy. High interface density with localised interfacial strain offers effective sinks, suppressing defect populations compared to the counterpart with lower interface density. Meanwhile, atomic resolution spectroscopy and irradiation with in-situ transmission electron microscopy show that the disordering stems from Al-rich and Ti-rich sublattices mixing in the initial L2₁-Ni₂AlTi structure below 500°C, forming metastable B2-Ni(Al,Ti). Combined, the high interface density and radiation-induced intermetallic disordering underpin the remarkable radiation tolerance, demonstrating the IDS concept as a promising radiation-resistant materials design strategy.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"3 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897545","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":"Liquid-liquid phase transition and chemical phase separation in Cu-Zr-Al-Y bulk glass-forming supercooled liquid","authors":"H.R. Jiang, M. Frey, N. Neuber, Q. Wang, W.F. Lu, L.M. Ruschel, G.Y. Sun, I. Gallino, B. Zhang, G. Wang, R. Busch, J. Shen, Y. Yang","doi":"10.1016/j.actamat.2025.121090","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121090","url":null,"abstract":"Anomalous exothermic peaks (AEPs) before crystallization in metallic supercooled liquids are commonly attributed to chemical phase separation (CPS) or structural changes due to polyamorphic liquid-liquid phase transition (LLPT). In this work, we present experimental evidence of the simultaneous occurrence of LLPT and CPS during the anomalous exothermic reaction in a supercooled Cu-Zr-Al-Y liquid. The CPS results from the positive enthalpy of mixing between Y and Zr, while LLPT, characterized by medium-range structural ordering, originates from the two-phase field (fragile and strong phases) centered around Cu₅₀Zr₅₀ in the Cu-Zr system. These two aspects interact with each other and are considered to be a key factor in stabilizing the supercooled liquid against crystallization. To describe the structural and chemical evolutions in the supercooled liquid, we propose schematic Gibbs free energy surfaces for the (Cu, Al)-(Zr, Al)-Y pseudo-ternary system that incorporate both the two-phase field of LLPT and the local maximum of the CPS in the Y direction. The results of this work not only enrich our understanding of anomalous thermophysical signals in the supercooled liquid but also offer insights into the development of bulk metallic glasses with superior glass-forming ability and thermal stability.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"38 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897544","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":"Extraordinary hardening-by-annealing in bulk ultrafine grained magnesium with ultra-low yttrium addition","authors":"Ruixiao Zheng, Maowen Liu, Junping Du, Hongbo Xie, Wu Gong, Yangyang Cheng, Shigenobu Ogata, Nobuhiro Tsuji","doi":"10.1016/j.actamat.2025.121098","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121098","url":null,"abstract":"Hall-Petch law fails when grains smaller than a critical size (e.g., 10∼30 nm for copper and iron), due to grain boundary (GB) kinetics-dominated plasticity. To enhance strength, improving GB stability is a consideration. However, this often requires a significant amount of alloying elements, posing resource challenges. Additionally, practical fabrication of extremely fine grains is still an issue. In our study, we firstly demonstrate a remarkable hardening-by-annealing phenomenon in magnesium (Mg) with relatively large grain sizes of 0.2∼0.5 μm, even with ultra-low yttrium (Y) addition (&lt;0.3 at.%). We reveal that annealing induces GB segregation/relaxation, effectively limiting the GB kinetics and promoting dislocation-dominated plasticity. Furthermore, the accompanying dislocation annihilation hinders deformation due to dislocation scarcity. As a result, we discovered extraordinary hardening (247% increase in yield strength) in bulk ultrafine grained Mg-Y ultra-dilute alloy. This work offers a promising avenue for developing energy- and resource-efficient sustainable Mg alloys with superior mechanical properties.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"9 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897548","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":"Dissociation and motion of dislocations in a C14 Laves phase","authors":"Yongchao Zhang, Liyuan Sheng","doi":"10.1016/j.actamat.2025.121096","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121096","url":null,"abstract":"Laves phases are typical complex intermetallic compounds, and the mechanisms governing dislocation motion within these crystals remain poorly understood. In this study, we employed aberration-corrected scanning transmission electron microscopy to directly observe the dissociation and movement of &lt;<strong>c</strong>+<strong>a</strong>&gt; dislocations in a hexagonal C14 Laves phase subjected to high-temperature compression. These dislocations exhibit multiple dissociations, with their behavior shifting from being controlled by long-range lattice translational order to short-range configurations associated with local atomic environments. A twin-synchroshear mechanism is proposed to promote the migration of multilayer atoms during the 1/6&lt;2-203&gt; dislocation climb on basal planes. Our experimental findings in the C14 Laves phase suggest that the most effective plastic deformation in complex structures arises from dislocations that facilitate local structural transformations while maintaining long-range lattice order. This insight advances our understanding of dislocation behavior and plasticity in complex intermetallic compounds.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"50 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897599","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":"Multi-Modal Characterization of the B2 Phase in the Ta-Re Binary System","authors":"Bryan J. Crossman, Junxin Wang, Loic Perrière, Si Athena Chen, Jean-Philippe Couzinié, Maryam Ghazisaeidi, Michael J. Mills","doi":"10.1016/j.actamat.2025.121097","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121097","url":null,"abstract":"The energy and transportation industries demand materials that retain their mechanical property at high temperatures. Refractory complex concentrated alloys (RCCAs) with a BCC + B2 microstructure offer a potential solution, where maintaining the high temperature mechanical properties can be achieved by precipitation strengthening. This depends on the B2 phase in RCCAs being thermodynamically stable with a high solvus temperature. Recently, we predicted the high temperature stability of the B2 structure in the Ta-Re binary system, using density functional theory. Here, we provide experimental evidence for the existence of this phase for the first time, using a &lt;span&gt;&lt;span style=\"\"&gt;&lt;/span&gt;&lt;span data-mathml='&lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow is=\"true\"&gt;&lt;mi is=\"true\"&gt;T&lt;/mi&gt;&lt;msub is=\"true\"&gt;&lt;mi is=\"true\"&gt;a&lt;/mi&gt;&lt;mn is=\"true\"&gt;65&lt;/mn&gt;&lt;/msub&gt;&lt;mi is=\"true\"&gt;R&lt;/mi&gt;&lt;msub is=\"true\"&gt;&lt;mi is=\"true\"&gt;e&lt;/mi&gt;&lt;mn is=\"true\"&gt;35&lt;/mn&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;' role=\"presentation\" style=\"font-size: 90%; display: inline-block; position: relative;\" tabindex=\"0\"&gt;&lt;svg aria-hidden=\"true\" focusable=\"false\" height=\"2.317ex\" role=\"img\" style=\"vertical-align: -0.582ex;\" viewbox=\"0 -747.2 4075.6 997.6\" width=\"9.466ex\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"&gt;&lt;g fill=\"currentColor\" stroke=\"currentColor\" stroke-width=\"0\" transform=\"matrix(1 0 0 -1 0 0)\"&gt;&lt;g is=\"true\"&gt;&lt;g is=\"true\"&gt;&lt;use xlink:href=\"#MJMATHI-54\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;g is=\"true\" transform=\"translate(704,0)\"&gt;&lt;g is=\"true\"&gt;&lt;use xlink:href=\"#MJMATHI-61\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;g is=\"true\" transform=\"translate(529,-150)\"&gt;&lt;use transform=\"scale(0.707)\" xlink:href=\"#MJMAIN-36\"&gt;&lt;/use&gt;&lt;use transform=\"scale(0.707)\" x=\"500\" xlink:href=\"#MJMAIN-35\" y=\"0\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;/g&gt;&lt;g is=\"true\" transform=\"translate(2041,0)\"&gt;&lt;use xlink:href=\"#MJMATHI-52\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;g is=\"true\" transform=\"translate(2801,0)\"&gt;&lt;g is=\"true\"&gt;&lt;use xlink:href=\"#MJMATHI-65\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;g is=\"true\" transform=\"translate(466,-150)\"&gt;&lt;use transform=\"scale(0.707)\" xlink:href=\"#MJMAIN-33\"&gt;&lt;/use&gt;&lt;use transform=\"scale(0.707)\" x=\"500\" xlink:href=\"#MJMAIN-35\" y=\"0\"&gt;&lt;/use&gt;&lt;/g&gt;&lt;/g&gt;&lt;/g&gt;&lt;/g&gt;&lt;/svg&gt;&lt;span role=\"presentation\"&gt;&lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow is=\"true\"&gt;&lt;mi is=\"true\"&gt;T&lt;/mi&gt;&lt;msub is=\"true\"&gt;&lt;mi is=\"true\"&gt;a&lt;/mi&gt;&lt;mn is=\"true\"&gt;65&lt;/mn&gt;&lt;/msub&gt;&lt;mi is=\"true\"&gt;R&lt;/mi&gt;&lt;msub is=\"true\"&gt;&lt;mi is=\"true\"&gt;e&lt;/mi&gt;&lt;mn is=\"true\"&gt;35&lt;/mn&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;&lt;/span&gt;&lt;script type=\"math/mml\"&gt;&lt;math&gt;&lt;mrow is=\"true\"&gt;&lt;mi is=\"true\"&gt;T&lt;/mi&gt;&lt;msub is=\"true\"&gt;&lt;mi is=\"true\"&gt;a&lt;/mi&gt;&lt;mn is=\"true\"&gt;65&lt;/mn&gt;&lt;/msub&gt;&lt;mi is=\"true\"&gt;R&lt;/mi&gt;&lt;msub is=\"true\"&gt;&lt;mi is=\"true\"&gt;e&lt;/mi&gt;&lt;mn is=\"true\"&gt;35&lt;/mn&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/script&gt;&lt;/span&gt; alloy. Despite Ta-Re binary phase diagrams predicting a single-phase BCC microstructure for &lt;span&gt;&lt;span style=\"\"&gt;&lt;/span&gt;&lt;span data-mathml='&lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow is=\"true\"&gt;&lt;mi is=\"true\"&gt;T&lt;/mi&gt;&lt;msub is=\"true\"","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"26 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143893903","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":"Orientation relationships of seed crystal-induced Al2O3/GdAlO3 eutectic ceramics","authors":"Yujie Zhong, Ye Yuan, Huadong Li, Shanna Xu, Yuntao Xi, Xu Wang","doi":"10.1016/j.actamat.2025.121094","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121094","url":null,"abstract":"Al₂O₃-based directional solidified eutectic ceramics (DSECs) have long faced limitations in fracture toughness, hindering their practical applications. To address this challenge, we propose an innovative approach utilizing single-crystal <em>c</em>-sapphire as a seed to fabricate dual-phase Al₂O₃/GdAlO₃ (GAP) DSECs. The resulting eutectic ceramics exhibit coexisting regular fibrous and irregular Chinese script morphological features, where the crystallographic orientation of Al₂O₃ is inherited from the seed while GAP develops dual growth orientations governed by epitaxial relationships with Al₂O₃. Theoretical analyses based on interface matching principles reveal that low planar mismatching (&lt;12%) critically enables the successful synthesis of this heterostructure. The designed orientation modulation coupled with tailored eutectic morphology synergistically enhances mechanical performance, achieving a hardness of 18.5 ± 0.5 GPa and fracture toughness of 5.3 ± 0.6 MPa·m^1/2. This work establishes a paradigm for optimizing mechanical properties in directional solidification systems through crystallographic orientation control.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"19 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143889824","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":"Corrigendum to “A Combined DFT and NPD Approach to Determine the Structure and Composition of the ε-Phase of Tungsten Boride” [Acta Materialia 259 (2023) 119282]","authors":"S.S. Setayandeh, J.H. Stansby, E.G. Obbard, M.I. Brand, D.M. Miskovic, K.J. Laws, V.K. Peterson, S. Cetinkaya, J.O. Astbury, C.L. Wilson, S. Irukuvarghula, P.A. Burr","doi":"10.1016/j.actamat.2025.121067","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121067","url":null,"abstract":"The authors regret &lt;the oversight in the original manuscript regarding the author list, which has now been revised&gt;.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"52 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143890261","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":"Tunable and anomalous electrocaloric behaviors in Bi0.5Na0.5TiO3-based relaxor enabled by dynamics of polar nanoregions","authors":"Feng Li ,&nbsp;Xuan Wang ,&nbsp;Mingsheng Long ,&nbsp;Daniel Q. Tan ,&nbsp;Lei Shan ,&nbsp;Chunchang Wang ,&nbsp;Haixue Yan","doi":"10.1016/j.actamat.2025.121093","DOIUrl":"10.1016/j.actamat.2025.121093","url":null,"abstract":"<div><div>Eco-friendly electrocaloric (EC) refrigeration technology, by virtue of its high efficiency and a cutting-edge decarbonization strategy, has become a promising alternative for vapor compression refrigeration. The EC effect in Bi_0.5Na_0.5TiO₃-based ferroelectric is prominent since their high ferroelectricity and flexible phase structure regulation. However, the underlying mechanisms responsible for high and anomalous EC performances in Bi_0.5Na_0.5TiO₃-based ceramics are not fully addressed. In this work, a high Δ<em>T</em> with 0.66–0.94 K and a large temperature span (Δ<em>T</em>_span) of 50–60 K are achieved in Bi_0.5Na_0.5TiO₃-Ba(Ti, Hf)O₃-NaNbO₃ system. The EC effect exhibits a tunable behavior, i.e., the temperature corresponds to the maximal Δ<em>T</em> value (Δ<em>T</em>_max) gradually decreases via downshifting critical freezing temperature (<em>T_f</em>). This phenomenon is accompanied by the collapse of domains into polar nanoregions (PNRs) and a reduction in correlation length, as supported by inverse fast Fourier transformation analysis and piezoelectric force microscopy images. Furthermore, the asymmetrical EC profiles with a large gap between exothermic and endothermic EC peaks near <em>T_f</em> are largely ascribed to the time effect for PNRs evolution, as demonstrated by time-resolved pulsed dielectric spectra and customized polarization test. Interestingly, high Δ<em>T</em> is maintained as <em>T</em> ≥ <em>T_f</em> but sharply declines as <em>T</em> &lt; <em>T_f</em>, which originates from a crossover from activated to frozen ferroelectric state. These findings reveal that PNRs dynamics strongly impact on EC performances, with high Δ<em>T</em> and broad Δ<em>T</em>_span primarily arising from highly polar and mobile PNRs. This work not only gives a deep insight into EC behaviors in Bi_0.5Na_0.5TiO₃-based ceramics but also proposes a refreshing strategy for optimizing EC performance with regulating PNRs dynamics.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"293 ","pages":"Article 121093"},"PeriodicalIF":8.3,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143885258","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 Behavior and Size–Dependent Strength of Small Noble-Metal Nanoparticles","authors":"Ruikang Ding, Ashlie Martini, Tevis D.B. Jacobs","doi":"10.1016/j.actamat.2025.121092","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121092","url":null,"abstract":"While metal nanoparticles are foundational to many advanced technologies, the instability of small particles limits their performance and lifetime. Extensive prior work has demonstrated size-dependent behavior, including “smaller-is-stronger”, “smaller-is-weaker”, and “liquid-like deformation”. However, mechanistic understanding of deformation processes has been hampered by the difficulty of characterizing nanoparticles as they fail. Here, we have compressed nanoparticles to failure with <em>in situ</em> transmission electron microscopy, linking their strength to direct observation of failure mechanisms. More than 250 tests, conducted on particles of Au, Ag, and Pt with sizes ranging from 3 to 130 nm, reveal a complex, non-monotonic dependence of strength on particle size. Deformation in larger particles (130 nm down to approximately 15 nm) is carried by dislocations nucleating from the surface. Without any observable change in mechanism, the nanoparticles first exhibit strengthening with decreasing size, reach a peak strength at around 30–60 nm, then show weakening. Deformation in intermediate-size particles (15 to approximately 5 nm) exhibits a mix of plasticity and diffusive deformation. Finally, the very smallest particles, with single-digit-nanometer sizes, exhibit homogeneous diffusive deformation that contradicts recent theories, and is instead well described by the zero-creep analysis. Overall, this work reveals the regimes and mechanisms underlying nanoparticle failure, across sizes and across materials.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"223 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143890239","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}