Intermetallics最新文献

{"title":"High-temperature tensile and fatigue properties of Ti-48Al-2Cr-2Nb alloy additively manufactured via twin-wire directed energy deposition-arc","authors":"Wenlu Zhou ,&nbsp;Chen Shen ,&nbsp;Lin Wang ,&nbsp;Ying Li ,&nbsp;Ting Zhang ,&nbsp;Jianwen Xin ,&nbsp;Yuhan Ding ,&nbsp;Danqi Zhang ,&nbsp;Yuelong Zhang ,&nbsp;Fang Li ,&nbsp;Xueming Hua","doi":"10.1016/j.intermet.2025.108833","DOIUrl":"10.1016/j.intermet.2025.108833","url":null,"abstract":"<div><div>Recently, additive manufacturing of titanium aluminide has attracted widespread attention. Since titanium aluminide is an ideal structure material for high-temperature, corresponding mechanical properties are of great significance. In present work, tensile properties from 25 °C to 1050 °C and fatigue properties at 650 °C were examined for the first time on twin-wire directed energy deposition-arc (TW-DED-arc) manufactured Ti-48Al-2Cr-2Nb (TiAl-4822) alloy. Importantly, fracture characteristics and deformation mechanisms were systematically investigated. Similar with extensively investigated titanium aluminide, TW-DED-arc manufactured TiAl-4822 alloy generally tends to decrease strength while increase elongation versus temperature during tensile process. Meanwhile, anomalous increase of strength is detected at 750 °C, and brittle-to-ductile transition temperature (BDTT) is around 850 °C. At 25 °C and 550 °C, γ/α₂ lamellar interface and lamellar colony boundary as well as special microstructures are weak positions and susceptible to microcracking, and mechanical twining dominates deformation mode. By comparison, in temperature range of 650 °C–950 °C, γ/α₂ interface and colony boundary are weaker, while deformation mechanism shifts to mechanical twinning and dislocation slip. Moreover, dynamic recrystallization (DRX) starts at 850 °C and further affects tensile behaviors, especially at 1050 °C. The fatigue limit (10⁷ cycles) at 650 °C is approximately 335 MPa, ratio of which to tensile strength is calculated to be 0.71, indicating good fatigue resistance of as-manufactured TiAl-4822 alloy. Irrespective of stress level, crack prefer to initiate and propagate at γ/α₂ interface and colony boundary. Both mechanical twining and dislocation slip are activated during fatigue process, but their morphologies vary with stress level. In sum, these findings provide a valuable reference for mechanical properties of additively manufactured titanium aluminide.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"184 ","pages":"Article 108833"},"PeriodicalIF":4.3,"publicationDate":"2025-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144071131","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-driven property evolution in metal additive manufactured nickel alloy","authors":"R. Raghu ,&nbsp;P. Chandramohan ,&nbsp;D. Pradeesh kumar ,&nbsp;Amar Singh","doi":"10.1016/j.intermet.2025.108834","DOIUrl":"10.1016/j.intermet.2025.108834","url":null,"abstract":"<div><div>The laser Powder Bed Fusion (LPBF) process is vital for aerospace sector to produce components with intricate geometry for better performance. In the present study, the nickel-based superalloy CM247LC was manufactured through LPBF. Microscopically, alloy revealed the presence of carbides. In the longitudinal section, Electron Backscatter Diffraction (EBSD) exposed elongated grains and in transverse section, equiaxed clusters. Rate of cooling during solidification was calculated to be approximately 10⁶ K/s. Yield strength of the samples found higher compared to the previous research. Sources of higher strength are interpreted as higher precipitate concentrations, dislocation density, finer cellular structure, and γ′ inside cells.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"184 ","pages":"Article 108834"},"PeriodicalIF":4.3,"publicationDate":"2025-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144071132","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":"Vacuum plasma sprayed AlCoCrFeNi high-entropy alloy bond Coating: Vacuum heat-treatment, microstructure evolution and oxidation behavior analysis","authors":"Hanfang Zhang ,&nbsp;Xiao Zhang ,&nbsp;Jun Zhang ,&nbsp;Mingming Pan","doi":"10.1016/j.intermet.2025.108836","DOIUrl":"10.1016/j.intermet.2025.108836","url":null,"abstract":"<div><div>The AlCoCrFeNi high-entropy alloy (HEA) bond coating is fabricated using vacuum plasma spray (VPS) technology, followed by a vacuum heat treatment (VHT) at 1050 °C for 5 h. This study rigorously investigates the effects of the VHT process on the microstructural evolution and oxidation resistance of the AlCoCrFeNi coating. The experimental findings indicate that both the as-sprayed and heat-treated coatings develop thermally grown oxide (TGO) layers predominantly composed of α-Al₂O₃ under oxidation conditions up to 1000 °C. Notably, the VHT-treated coating exhibits enhanced oxidation resistance, showing a 12.3 % reduction in TGO layer thickness after 50 h of oxidation at 1000 °C, compared to its untreated counterpart. This improvement is attributed to the microstructural changes during VHT, including grain coarsening and a decrease in grain boundary density, which collectively reduce the diffusion of Al ions outward. Additionally, phase analysis demonstrates that the AlCoCrFeNi coating transitions from an initial BCC structure to a BCC + FCC + σ-phase following vacuum heat treatment. The emergence of the FCC phase leads to a 23 % reduction in coating hardness (from 506.1 HV to 388.8 HV), which aids in stress relaxation at the TGO/coating interface and reduces the likelihood of crack initiation. Overall, this research, which offers a simple and effective method for enhancing the oxidation resistance of high entropy alloys.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"184 ","pages":"Article 108836"},"PeriodicalIF":4.3,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144069445","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":"Characterization of hot deformation of FeCoCrNiAl0.1 high entropy alloy: 3D processing maps, FEM numerical simulation and microstructure evolution","authors":"Bo Li ,&nbsp;Xiuyu Yu ,&nbsp;Zhicheng Huang ,&nbsp;Zhaojie Chu ,&nbsp;Han Yang ,&nbsp;Qinyi Zhu ,&nbsp;Xicong Ye ,&nbsp;Dong Fang ,&nbsp;Youlu Yuan","doi":"10.1016/j.intermet.2025.108821","DOIUrl":"10.1016/j.intermet.2025.108821","url":null,"abstract":"<div><div>To investigate the hot deformation and dynamic recrystallization (DRX) behavior of FeCoCrNiAl_0.1 high-entropy alloy (HEA), hot compression tests were conducted under varying temperatures range of 950–1100 °C with strain rates range of 0.001 and 1 s⁻¹. FeCoCrNiAl_0.1 HEA exhibit distinct DRX characteristics, synergistically controlled by dynamic recovery (DRV) and DRX. The hot processing map indicates that the studied alloy exhibits an optimal hot processing window of 1000–1100 °C/0.001–0.02 s⁻¹. According to finite element model (FEM), DRX distribution is temperature and strain-rate-dependent. The DRX region expands radially from core to peripheral with increasing temperature or decreasing strain rate. Microstructural evolution analysis reveals that the studied alloy exhibits pronounced DRV and DRX characteristics during hot deformation. DRX primarily proceeds through Continuous Dynamic Recrystallization (CDRX) driven by subgrain rotation and Discontinuous Dynamic Recrystallization (DDRX) through grain boundary bulging nucleation. As strain rate decreases or temperature increases, the studied alloy exhibits a grain coarsening and substantial dislocation density reduction. The grain orientation evolves from the typical R texture {134}&lt;211&gt; to the Cube texture {001}&lt;100&gt;, and this texture transition facilitates the progression of DRX.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108821"},"PeriodicalIF":4.3,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143948739","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":"Bauschinger effect on high entropy alloy under cyclic deformation","authors":"Hoang-Giang Nguyen ,&nbsp;Sheng-Joue Young ,&nbsp;Thanh-Dung Le ,&nbsp;Thi-Nhai Vu ,&nbsp;Te-Hua Fang","doi":"10.1016/j.intermet.2025.108830","DOIUrl":"10.1016/j.intermet.2025.108830","url":null,"abstract":"<div><div>This study employs molecular dynamics (MD) simulations to examine materials with comparable tension-compression behavior but markedly different cyclic fatigue performances. The findings reveal that the cyclic fatigue properties of AlCoCrCuFeNi high-entropy alloys (HEAs) are primarily governed by microscopic deformation mechanisms, particularly dislocation slip modes, which subtly affect initial work hardening. However, the slight initial differences in work hardening affected by the butterfly and Bauschinger effects gradually accumulate and intensify with repeated fatigue cycling. As the number of loading cycles increases, β-asymmetry steadily declines. Interactions between partial dislocations and stacking faults (SFs) at lower temperatures disrupt the lattice structure and impede dislocation reversal, thereby diminishing the Bauschinger effect. This mechanism contributes to marked variations in fatigue life and cyclic stress response.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108830"},"PeriodicalIF":4.3,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144068775","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":"Investigation of microstructure evolution and nanoindentation hardness of an oxygen-doped Ti35Zr35Hf20Nb10 nanograined multi-principal element alloy","authors":"Rong Huang ,&nbsp;Zongde Kou ,&nbsp;Song Tang ,&nbsp;Shimao Lv ,&nbsp;Gerhard Wilde ,&nbsp;Si Lan ,&nbsp;Tao Feng","doi":"10.1016/j.intermet.2025.108826","DOIUrl":"10.1016/j.intermet.2025.108826","url":null,"abstract":"<div><div>In this study, an oxygen-doped nominal component of (Ti₃₅Zr₃₅Hf₂₀Nb₁₀)₉₈O₂ nanograined multi-principal element alloy (NG-MPEA) with an average grain size of about 50 nm was synthesized via inert gas condensation (IGC). Moreover, the mechanical properties and microstructural evolution of the alloys were systematically investigated. The as-prepared samples (as-IGC) are composed of two phases with body-centered cubic (bcc) and hexagonal close-packed (hcp) structures. The samples were annealed to regulate the microstructure. The results demonstrate that when annealed at temperatures below 450 °C, the dual-phase structure composed of bcc and hcp phases was maintained. However, when annealed at 650 °C, a phase transformation of bcc to nano-sized ordered ω’ were observed. The nanoindentation hardness of the NG-MPEA increases from 4.5 GPa to 6.3 GPa after annealing at 450 °C and further increases to 7.6 GPa after annealing at 650 °C. Compared with the as-IGC state, the hardness increased by 69 %. The relationship between microstructure evolution and nanoindentation hardness was further discussed. This work provides an effective approach for enhancing the hardness of bulk NG-MPEAs by adjusting their microstructure.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108826"},"PeriodicalIF":4.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143948738","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":"Corrosion mechanism of CrMnFeCoNi high entropy alloy in nitric acid solution","authors":"Feng Han ,&nbsp;Chunyang Li ,&nbsp;Chenghao Li ,&nbsp;Jiacai Wang ,&nbsp;Chaobo Xia ,&nbsp;Xiubo Li ,&nbsp;Long Xue ,&nbsp;Caimei Wang","doi":"10.1016/j.intermet.2025.108822","DOIUrl":"10.1016/j.intermet.2025.108822","url":null,"abstract":"<div><div>The corrosion behavior and passive film characteristics of CrMnFeCoNi high entropy alloy (HEA) in HNO₃ solution (0.1 M, 1 M, 4 M and 6 M) was investigated. The electrochemical test results demonstrated enhanced corrosion resistance with increasing HNO₃ concentration, evidenced by higher corrosion potential, lower passivation current density, and larger impedance modulus value. XPS and finite element analysis confirmed that the improved corrosion resistance in 6 M HNO₃ was attributed to a Cr₂O₃-rich passive film (22.5 %), formed via autocatalytic redox reactions and stabilized by Mn²⁺ inhibiting Cr(III) oxidation.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108822"},"PeriodicalIF":4.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143942355","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":"Achieving an excellent strength-ductility synergy in a medium-entropy alloy by a suitable thermo-mechanical processing","authors":"Lei Wang ,&nbsp;Haoshuai Qiang ,&nbsp;Sihan Liu ,&nbsp;Mengjie Zhao ,&nbsp;Gang Liu ,&nbsp;Yunpeng Zhang ,&nbsp;Jun Shen ,&nbsp;Guojun Zhang","doi":"10.1016/j.intermet.2025.108828","DOIUrl":"10.1016/j.intermet.2025.108828","url":null,"abstract":"<div><div>In this study, we present a Co₂Ni₂Cr medium-entropy alloy (MEA) co-doped with Al/Mo, and systematically regulate its microstructure through thermo-mechanical processing. A representative (Co₂Ni₂Cr)₈₈Al₈Mo₄ MEA, fabricated via cold rolling followed by annealing at 765 °C, exhibits an excellent strength-ductility synergy. It achieves a high yield strength of ∼1150 MPa, an ultimate tensile strength of ∼1397 MPa, and maintains a good ductility of ∼17 %. The representative MEA undergoes partial recrystallization, with high-<strong>density L1₂ nanoparticles uniformly distributed in both recrystallized and non-recrystallized regions. Furthermore, EBSD analysis reveals the presence of high-density dislocations within the non-recrystallized region.</strong> Therefore, precipitation strengthening by L1₂ nanoparticles and dislocation strengthening are likely the primary mechanisms contributing to the high yield strength observed in the representative MEA. Simultaneously, its excellent ductility can be attributed to the highly coherent two-phase interface, the presence of high-density microbands and Lomer-Cottrell (LC) locks, as well as a certain proportion of recrystallized regions. Therefore, this study presents an effective design strategy to achieve an excellent strength-ductility synergy in a MEA through optimized thermo-mechanical processing.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108828"},"PeriodicalIF":4.3,"publicationDate":"2025-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143931447","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":"Machine learning-accelerated prediction of mechanical and microstructural properties of BCC Fe–Cr–Ni–Al high-entropy alloys across the full compositional space","authors":"Jingteng Xue ,&nbsp;Jingtao Huang ,&nbsp;Zhonghong Lai ,&nbsp;Nan Qu ,&nbsp;Yong Liu ,&nbsp;Jingchuan Zhu","doi":"10.1016/j.intermet.2025.108827","DOIUrl":"10.1016/j.intermet.2025.108827","url":null,"abstract":"<div><div>This study employs machine learning to accelerate the computation of mechanical properties and microstructural characteristics of BCC FeCrNiAl high-entropy alloys across the entire compositional range. Initially, 49 representative compositional points were selected within the compositional space, encompassing unary to quaternary alloys. Based on ab initio calculations using density functional theory, theoretical Young's modulus, bulk modulus, brittleness-toughness indicators, deviation of atomic positions, shape deformation ratio, and density were obtained. The Categorical Boosting algorithm was then used to develop a composition-property model, predicting properties across the full compositional space. Alloy properties were mapped onto a 2-D plane for systematic analysis, and the SHAP method was used to quantify the influence of individual elements. It was found that fine-tuning the composition can achieve simultaneous optimization of strength and toughness. Specifically, adjusting the Cr content at high FeNi levels effectively enhances ductility, while keeping Al content within the maximum permissible range is crucial for engineering applications that require a balance between strength and density. Further exploration was conducted on the characteristics of the FeAl(CrNi)x series alloys. This study highlights the potential of machine learning to accelerate ab initio calculations methods for complex alloys, improving efficiency and providing a basis for designing and optimizing FeCrNiAl HEAs.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108827"},"PeriodicalIF":4.3,"publicationDate":"2025-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143928456","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":"The strengthening mechanism of Al-Mg-Si-Cu alloy laser-arc hybrid welds with Ni alloying","authors":"Xiaming Chen ,&nbsp;Jia Song ,&nbsp;Xiaonan Wang ,&nbsp;Shuncun Luo ,&nbsp;Nagaumi Hiromi","doi":"10.1016/j.intermet.2025.108824","DOIUrl":"10.1016/j.intermet.2025.108824","url":null,"abstract":"<div><div>The strategic incorporation of nickel alloying in weld seams was investigated as a means to improve both the static and dynamic mechanical properties of high-performance Al-Mg-Si-Cu alloys laser-arc welds. Microstructural characterization revealed that Ni addition induced dual strengthening mechanisms: precipitation of Al₃Ni particles and solid solution strengthening through Ni dissolution, accompanied by significant grain refinement. However, microstructural analysis revelaed a critical threshold effect: at Ni concentrations exceeding 1.8 wt%, Al₃Ni particles formed continuous networks that initiated microcrack propagation under stress, ultimately leading to macrocrack formation in weld seam containing 3.6 wt% and 6.0 wt% Ni. Optimal mechanical performance was achieved at a 1.8 wt% Ni addition, where the weld seam exhibited a 23 % increase in yield strength (239 ± 2 MPa) and an 11 % enhancement in tensile strength (281 ± 3 MPa) compared to non-alloyed counterparts. The high temperature baking process further improved joint efficiency through precipitation hardening, with nano-scale βʹ particles, increasing the welded joint coefficient to 0.78. The synergistic combination of grain boundary strengthening, precipitation hardening, and solid solution strengthening resulted in exceptional fatigue performance, demonstrating a fatigue limit of 147 MPa (<em>R</em> = 0.1, <em>N</em> = 10⁷) and a fatigue ratio of 0.46 exceeding those reported in previous studies on similar alloy systems.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108824"},"PeriodicalIF":4.3,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143922609","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}