Intermetallics最新文献

{"title":"Crack formation mechanisms in laser-directed energy deposited high-Nb TiAl alloys","authors":"Yan Liu,&nbsp;Kai Hu,&nbsp;Jun Song,&nbsp;Xu Zheng,&nbsp;Yu Song,&nbsp;Bo Song,&nbsp;Yusheng Shi","doi":"10.1016/j.intermet.2025.108975","DOIUrl":"10.1016/j.intermet.2025.108975","url":null,"abstract":"<div><div>In the additive manufacturing (AM) of TiAl alloys, cracking is an important bottleneck restricting the development of TiAl alloys. This study systematically investigates crack nucleation locations and formation mechanisms in monolayer deposition samples through comprehensive characterization using Electron Back-Scattered Diffraction (EBSD) and Scanning Electron Microscopy (SEM). The laser direct energy deposition (LDED)-fabricated Ti-47.5Al-6.8Nb-0.2W alloy exhibits two distinct types of cracks: macrocracks and microcracks. Macrocracks primarily originate from the brittleness of the α₂ phase and the residual stresses induced by rapid heating and cooling during the printing process, showing no significant correlation with the microstructure of the TiAl deposited layer. These macrocracks nucleate at the diffusion layer between the Ti6Al4V (TC4) substrate and the TiAl deposited layer, subsequently propagating through the entire deposited layer. In contrast, microcracks are closely associated with phase transformation effects. Specifically, the α₂→β₀ phase transformation generates transformation strain, leading to localized stress concentration and thereby promoting microcrack initiation. Furthermore, the inherent brittleness of the α₂ phase facilitates microcrack propagation. These findings provide critical insights into the cracking mechanisms in additively manufactured TiAl alloys, offering valuable guidance for process optimization and crack suppression strategies.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"187 ","pages":"Article 108975"},"PeriodicalIF":4.8,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145007577","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}

{"title":"Rejuvenation of a Zr-based metallic glass originates from strong icosahedral short-range order","authors":"Yunwei Cao,&nbsp;Yifan Yang,&nbsp;Jing Geng,&nbsp;Li Fan,&nbsp;Bo Shi","doi":"10.1016/j.intermet.2025.108980","DOIUrl":"10.1016/j.intermet.2025.108980","url":null,"abstract":"<div><div>When a Zr-based metallic glass (MG) is stimulated by cryogenic thermal cycling (CTC), its atomic icosahedral short-range order (ISRO) has a crucial impact on the evolution of its energy state, determining whether the system undergoes relaxation or rejuvenation. Through experiments and molecular dynamic simulations, it was found that CTC increases the degree of structural heterogeneity in the MG with strong ISRO, thereby introducing more free volume, inducing its rejuvenation, and enhancing its plasticity. However, for the MG with weak ISRO, its response to CTC is completely opposite, that is, relaxation and densification occur. The response of CTC is highly sensitive to the initial atomic short-range order of MG. This finding provides some insights into achieving high rejuvenation of MGs from the perspective of atomic cluster structure.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"187 ","pages":"Article 108980"},"PeriodicalIF":4.8,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144997660","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}

{"title":"L12-type Ni3Al-based high-entropy aluminides with superior strength-ductility: From design to criteria","authors":"Zheng Liu,&nbsp;Laiqi Zhang,&nbsp;Pengfei Zhao,&nbsp;Chao Wang","doi":"10.1016/j.intermet.2025.108979","DOIUrl":"10.1016/j.intermet.2025.108979","url":null,"abstract":"<div><div>L1₂-type Ni₃Al-based high-entropy aluminides (HEAs) with superior strength-ductility synergy exhibit great potential as advanced structural materials. Nevertheless, effective design method and phase formation criteria applicable to L1₂-type Ni₃Al-based HEAs remain elusive. In this study, the design method of L1₂-type Ni₃Al-based HEAs was systematically discussed from site preference of atoms, selection of multi-principal elements to determination of stoichiometric ratio. A series of L1₂-type Ni₃Al-based HEAs with excellent mechanical properties were successfully developed using this design strategy, and corresponding phase formation criteria were proposed. The designed alloys exhibited a high volume fraction of ordered L1₂ phase (&gt;75 %) and a small amount of disordered FCC phase. The as-cast HEAs-1 alloy showed excellent high yield strength (&gt;600 MPa) and ultimate tensile strength (&gt;1200 MPa) with large tensile elongation (&gt;35 %). Moreover, a new thermodynamic parameter, enthalpy-entropy ratio <span><math><mrow><mi>η</mi></mrow></math></span>, was established based on the pseudo-binary sublattice model. The formation of L1₂-type Ni₃Al-based HEAs is conducive within the ranges of <span><math><mrow><mi>η</mi><mo>≥</mo><mn>1.1</mn></mrow></math></span>, <span><math><mrow><msubsup><mi>δ</mi><mi>r</mi><mo>∗</mo></msubsup><mo>&lt;</mo><mn>3</mn><mo>%</mo></mrow></math></span>, <span><math><mrow><mn>4.5</mn><mo>%</mo><mo>&lt;</mo><msubsup><mi>δ</mi><mi>r</mi><mrow><mi>A</mi><mo>−</mo><mi>B</mi></mrow></msubsup><mo>&lt;</mo><mn>6.5</mn><mo>%</mo></mrow></math></span>, <span><math><mrow><mo>Δ</mo><msup><mi>χ</mi><mo>∗</mo></msup><mo>&lt;</mo><mn>5.5</mn><mo>%</mo></mrow></math></span>, <span><math><mrow><mn>6</mn><mo>%</mo><mo>&lt;</mo><mo>Δ</mo><msup><mi>χ</mi><mrow><mi>A</mi><mo>−</mo><mi>B</mi></mrow></msup><mo>&lt;</mo><mn>9.5</mn><mo>%</mo></mrow></math></span>, <span><math><mrow><msubsup><mi>σ</mi><mrow><mi>V</mi><mi>E</mi><mi>C</mi></mrow><mo>∗</mo></msubsup><mo>&lt;</mo><mn>1.1</mn></mrow></math></span>, <span><math><mrow><mn>2</mn><mo>&lt;</mo><msubsup><mi>σ</mi><mrow><mi>V</mi><mi>E</mi><mi>C</mi></mrow><mrow><mi>A</mi><mo>−</mo><mi>B</mi></mrow></msubsup><mo>&lt;</mo><mn>3</mn></mrow></math></span>, and <span><math><mrow><mn>8</mn><mo>&lt;</mo><mi>V</mi><mi>E</mi><msub><mi>C</mi><mrow><mi>t</mi><mi>o</mi><mi>t</mi></mrow></msub><mo>&lt;</mo><mn>8.5</mn></mrow></math></span>. The correctness and validity of the phase formation criteria were verified through the designed experiments. The criteria are simple and reliable, and can provide method and guidance for designing and developing advanced structural materials with superior mechanical properties.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"187 ","pages":"Article 108979"},"PeriodicalIF":4.8,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144997661","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}

{"title":"Eutectic growth mechanism and microstructure of rapidly solidified Co23.2Fe13.7Ni24.6Cr10.9Sn27.6 high-entropy alloy: Effects of solute drag","authors":"Yulong Liu ,&nbsp;Yeqing Wang ,&nbsp;Ke Fu ,&nbsp;Xin Jiao ,&nbsp;Liji Su ,&nbsp;Ye Tian ,&nbsp;Meng Liu ,&nbsp;Quan Xu ,&nbsp;Yuan Tong ,&nbsp;Lei Xu ,&nbsp;Changyun Li ,&nbsp;Zheng Chen","doi":"10.1016/j.intermet.2025.108983","DOIUrl":"10.1016/j.intermet.2025.108983","url":null,"abstract":"<div><div>Rapid solidification experiments on Co_23.2Fe_13.7Ni_24.6Cr_10.9Sn_27.6 eutectic high-entropy alloy (EHEA) were conducted by molten glass purification method and cyclic overheating techniques. Two solidification paths were identified. In the as-cast and low undercooling samples, the eutectic microstructure consisted of an FCC solid solution phase, M₃Sn₂ (M = Co, Ni) compounds with an HCP structure and BCC precipitates. The BCC precipitates disappeared at high undercoolings. A remarkably slow growth kinetics hindered by solute drag was discovered. The maximum growth velocity of the anomalous eutectic was 0.5797 m s⁻¹. Microstructural and quantitative elemental analyses indicate that the transition in eutectic growth mechanism is induced by the solute supersaturation with increasing undercooling. An orientation relationship (OR) of <span><math><mrow><msub><mrow><mo>&lt;</mo><mover><mn>1</mn><mo>‾</mo></mover><mn>01</mn><mover><mn>1</mn><mo>‾</mo></mover><mo>&gt;</mo></mrow><mtext>hcp</mtext></msub><mspace></mspace><mo>‖</mo><mspace></mspace><msub><mrow><mo>&lt;</mo><mn>100</mn><mo>&gt;</mo></mrow><mtext>bcc</mtext></msub></mrow></math></span> and <span><math><mrow><msub><mrow><mrow><mo>{</mo><mn>21</mn></mrow><mover><mn>3</mn><mo>‾</mo></mover><mrow><mn>1</mn><mo>}</mo></mrow></mrow><mtext>hcp</mtext></msub><mspace></mspace><mo>‖</mo><mspace></mspace><msub><mrow><mo>{</mo><mn>100</mn><mo>}</mo></mrow><mtext>bcc</mtext></msub></mrow></math></span> was determined between M₃Sn₂ (M = Co, Ni) compounds and BCC precipitates by transmission electron microscopy (TEM) analysis. Solute drag hinders the formation of the OR at the eutectic two phases, which is promoted by rapid solidification. Microhardness and uniaxial compression tests revealed that the increase in strength at low undercoolings was due to lamellar refinement. The anomalous eutectic structure exhibited low-stress brittle fracture, likely resulting from growth mechanism transition.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"187 ","pages":"Article 108983"},"PeriodicalIF":4.8,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144988772","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}

{"title":"Corrigendum to “On the calculation of the density of multi-component solid solutions” [Intermetallics 185 (2025) 108924]","authors":"Juan M. Montes,&nbsp;Fátima Ternero","doi":"10.1016/j.intermet.2025.108982","DOIUrl":"10.1016/j.intermet.2025.108982","url":null,"abstract":"","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"186 ","pages":"Article 108982"},"PeriodicalIF":4.8,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004211","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}

{"title":"Homogeneity of nano-sized Ni4Ti3 induced by dislocation distribution control to improve superelasticity in Ti-50.8 at.% Ni alloy","authors":"Yongqiang Yu ,&nbsp;Xiaofeng Xu ,&nbsp;Chao Wu ,&nbsp;Xudong Yan ,&nbsp;Yachong Zhou ,&nbsp;Zhicheng Wu ,&nbsp;Lai Wei ,&nbsp;Zhihui Zhang","doi":"10.1016/j.intermet.2025.108972","DOIUrl":"10.1016/j.intermet.2025.108972","url":null,"abstract":"<div><div>The homogeneous distribution of nano-sized Ni₄Ti₃ precipitates plays an important role in improving the superelasticity of NiTi alloys. In this study, electropulsing treatment (EPT) was utilized to control the dislocation distribution in Ti-50.8 at.% Ni alloy. A dislocation configuration with dislocation networks within the uniformly distributed subgrain boundaries was produced after 180 ms EPT. Homogeneously distributed nano-sized Ni₄Ti₃ precipitates were obtained after low-temperature aging (250 °C for 8 h). It was found that the dislocation configuration induced by 180 ms EPT could increase the nucleation site and promote the uniform precipitation of Ni₄Ti₃. Thus the high superelastic stability was achieved. After aging at 250 °C for 8 h, the residual strain of the EPT180+aging sample was 0.55 % after 20 loading-unloading cycles, obviously lower than that of the as-received (2.15 %, 20 cycles) and heat treatment + aging samples (2.21 %, 20 cycles).</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"186 ","pages":"Article 108972"},"PeriodicalIF":4.8,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144932296","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}

{"title":"Percolation threshold of TCP clusters governs relaxation dynamics in Cu-Zr metallic glass-forming liquids","authors":"Xiefu Zhang ,&nbsp;Zean Tian ,&nbsp;Yuanwei Pu","doi":"10.1016/j.intermet.2025.108978","DOIUrl":"10.1016/j.intermet.2025.108978","url":null,"abstract":"<div><div>The origin of the abrupt dynamic slowdown observed during the concealed liquid-solid transition at temperature <em>T</em>_<em>ls</em> in rapidly cooled Cu-Zr metallic liquids remains poorly understood. Here, we resolve this longstanding puzzle by combining molecular dynamics simulations with the largest standard cluster analysis (LaSCA) to establish a direct causal link between topological cluster percolation and relaxation dynamics. Our findings reveal that topologically close-packed (TCP) clusters with an average size (<em>S</em>_TCP) exceeding a critical threshold (&gt;3) trigger a dynamic arrest below <em>T</em>_<em>ls</em>. This arrest arises from cooperative atomic motions driven by the spatial percolation of TCP clusters, which dominate the structural evolution. The identified <em>S</em>_TCP threshold (3.0–4.0 across compositions) serves as a universal signature of rigidity onset in metallic glass-forming liquids. By bridging atomic-scale topological connectivity with macroscopic dynamics, this work provides a predictive framework for tailoring relaxation behavior in non-equilibrium alloys.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"186 ","pages":"Article 108978"},"PeriodicalIF":4.8,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144925217","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}

{"title":"Microstructure evolution and mechanical properties of electron beam welded AlCoCrFeNi2.1 eutectic high-entropy alloy/304 stainless steel joints","authors":"Likuo Zhu ,&nbsp;Guoqing Chen ,&nbsp;Xinyan Teng ,&nbsp;Zhanhua Gan ,&nbsp;Junhong Zhao ,&nbsp;Chen Yang ,&nbsp;Xuesong Leng","doi":"10.1016/j.intermet.2025.108971","DOIUrl":"10.1016/j.intermet.2025.108971","url":null,"abstract":"<div><div>The AlCoCrFeNi_2.1 eutectic high-entropy alloy has emerged as a promising candidate for advanced structural applications due to its exceptional strength and thermal stability. In contrast, 304 stainless steel is widely employed in industrial settings owing to its low cost, excellent corrosion resistance, and superior processability. In this study, dissimilar welding of AlCoCrFeNi_2.1 and 304 stainless steel was successfully performed using electron beam welding, and the influence of various welding parameters on joint microstructure and mechanical properties was systematically investigated. Microstructural analysis revealed that under moderate heat input conditions, second-phase particles precipitated within the weld, with Cr-rich nanoparticles embedded inside them, ultimately forming a dual-phase structure comprising FCC and B2 phases. In contrast, at high or low heat inputs, the weld region primarily exhibited a single-phase disordered FCC solid solution, with no second-phase formation. Mechanical testing showed that the joint produced under low heat input achieved a maximum tensile strength of 687 MPa, corresponding to 91 % of the 304SS base metal, along with a post-fracture elongation of 21.5 %. The enhanced strength is primarily attributed to grain refinement, Al-induced crystalline defects, and the triaxial stress constraint effect arising from the narrow nail-shaped weld geometry. These findings provide critical insights for the design of high-quality weld joints between AlCoCrFeNi_2.1and Fe-based structural materials.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"186 ","pages":"Article 108971"},"PeriodicalIF":4.8,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144932295","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}

{"title":"Improvement of intermetallic catalysts using surface segregation of third elements demonstrated by adding Cu to CoGa for selective hydrogenation of propyne","authors":"Sena Matsushita ,&nbsp;Kazuyuki Iwase ,&nbsp;Takayuki Kojima","doi":"10.1016/j.intermet.2025.108969","DOIUrl":"10.1016/j.intermet.2025.108969","url":null,"abstract":"<div><div>Intermetallic compounds can be novel catalysts due to unique atomic-ordered arrangements and electronic structures. However, their elemental set, composition, and crystal structure cannot be freely selected, which limits the tunability of catalytic properties. In this study, we demonstrated an improvement in catalytic properties by adding a third element to intermetallic catalysts using selective hydrogenation of propyne by CoGa with Cu addition as a model reaction and catalyst. The selectivity was drastically improved by 5 %Cu addition. The surface segregation of Cu was revealed and considered to result in an ensemble effect for the selectivity improvement. The addition of NiGa to Cu does not result in segregation. Since Cu-Ni is miscible, but Cu-Co is immiscible, the third element should likely be immiscible with one component of intermetallic catalysts to utilize a segregation effect for improving catalytic properties.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"186 ","pages":"Article 108969"},"PeriodicalIF":4.8,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144916315","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}

{"title":"Impact of laser scanning strategies on microstructure and mechanical properties of Ti2AlNb intermetallic alloy","authors":"Jianmei Kang ,&nbsp;Bingbing Sun ,&nbsp;Ma Qian ,&nbsp;Jinfu Li","doi":"10.1016/j.intermet.2025.108973","DOIUrl":"10.1016/j.intermet.2025.108973","url":null,"abstract":"<div><div>This study investigates the effects of laser scanning strategies on the microstructure and mechanical properties of the low-ductility Ti₂AlNb intermetallic alloy fabricated via laser-based powder bed fusion of metals (PBF-LB/M). Three bidirectional linear scanning strategies—67° rotation (0-R67), 90° rotation (0-R90), and 45° inclined followed by 90° rotation (45-R90) between adjacent layers—were employed, with all other PBF-LB/M parameters held constant. High-quality alloy samples with &lt;0.01 % porosity, free of visible lack-of-fusion defects and cracks, were successfully fabricated. The as-printed microstructures predominantly consisted of a single B2/β phase, with grain size influenced by the scanning strategy, although texture remained largely unchanged. The 45-R90 sample demonstrated the highest yield strength (980 MPa) and best elongation (13.1 %), attributed to reduced residual stress and a higher, concentrated Schmidt Factor (SF). After heat treatment (HT: solution treatment, water quenching, and ageing), all samples retained the B2/β grain morphology, with α₂ phases forming along grain boundaries and O phases distributed within the grains. The HT 0-R67 sample exhibited the best strength-ductility combination (1066 MPa, 5.47 %), attributed to randomly oriented B2/β-grain boundaries, thin α₂ precipitates, and the lowest average SF of the O phase precipitates. These findings highlight the critical role of laser scanning strategies in tailoring microstructure and optimizing the performance of Ti₂AlNb alloys in both as-printed and heat-treated conditions.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"186 ","pages":"Article 108973"},"PeriodicalIF":4.8,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144916314","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}