Intermetallics最新文献_第2页

Effect of interlayer on microstructure and mechanical properties of NiTi/TC4 dissimilar metal resistance spot welded joints 中间层对NiTi/TC4异种金属电阻点焊接头组织和力学性能的影响

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-02-03 DOI: 10.1016/j.intermet.2026.109179

Xiaolong Peng , Timing Zhang , Yi Xiong , Yunfa Deng , Zhikang Ye , Yuhua Chen , Jiaming Ni , Yang Shen , Shiyi Zhang , Jilin Xie

This study constructs an interface model based on electronic theory, identifying three distinct interlayers: Ni, Nb, and Cu. Research indicates that the NiTi/Cu interface exhibits the highest binding energy and work of separation, with increased electron density forming strong metallic bonds. It is hypothesized that joints containing Cu will demonstrate superior mechanical properties. Using resistance spot welding (RSW) technology, the addition of interlayers enables the joining of dissimilar metals NiTi and TC4. The study indicates that the interlayers promote melt nucleus growth and influence its morphology. The melt nucleus in Ni-containing joints exhibits an “M”-shaped morphology, while those in Cu- or Nb-containing joints are elliptical. Research reveals the presence of Intermetallic compounds (IMCs) between the direct weld and Ni-containing joints, which are the primary factor affecting joint strength. Joint mechanical properties initially increased then decreased with rising welding current. At I = 7 kA, the Cu-containing joint achieved maximum mechanical properties, fracture energy, and fusion diameter: tensile load 7.28 kN, fracture energy 6.62 J, and fusion diameter 3556 μm. No significant stress concentration was observed, consistent with simulation results. All joints exhibited interfacial failure. The fracture mode for the Cu-containing joint was ductile fracture; the Nb-containing joint showed a mixed ductile-brittle fracture; while the direct weld and Ni-containing joints exhibited brittle fracture.

本研究构建了一个基于电子理论的界面模型，确定了三个不同的中间层：Ni， Nb和Cu。研究表明，NiTi/Cu界面具有最高的结合能和分离功，随着电子密度的增加，形成较强的金属键。假设含Cu的接头具有较好的力学性能。采用电阻点焊（RSW）技术，添加中间层可以连接不同的金属NiTi和TC4。研究表明，中间层促进熔体核的生长，影响熔体核的形态。含ni接头的熔体核呈“M”形，而含Cu或nb接头的熔体核呈椭圆形。研究表明，直接焊缝与含镍接头之间存在金属间化合物（IMCs），是影响接头强度的主要因素。随着焊接电流的增大，接头力学性能先升高后降低。在I = 7 kA时，含cu接头的力学性能、断裂能和熔合直径最大，拉伸载荷为7.28 kN，断裂能为6.62 J，熔合直径为3556 μm。未观察到明显的应力集中，与模拟结果一致。所有接头均表现为界面破坏。含铜接头断裂方式为韧性断裂；含铌接头呈现韧脆混合断裂；直焊和含镍接头均表现为脆性断裂。

{"title":"Effect of interlayer on microstructure and mechanical properties of NiTi/TC4 dissimilar metal resistance spot welded joints","authors":"Xiaolong Peng , Timing Zhang , Yi Xiong , Yunfa Deng , Zhikang Ye , Yuhua Chen , Jiaming Ni , Yang Shen , Shiyi Zhang , Jilin Xie","doi":"10.1016/j.intermet.2026.109179","DOIUrl":"10.1016/j.intermet.2026.109179","url":null,"abstract":"<div><div>This study constructs an interface model based on electronic theory, identifying three distinct interlayers: Ni, Nb, and Cu. Research indicates that the NiTi/Cu interface exhibits the highest binding energy and work of separation, with increased electron density forming strong metallic bonds. It is hypothesized that joints containing Cu will demonstrate superior mechanical properties. Using resistance spot welding (RSW) technology, the addition of interlayers enables the joining of dissimilar metals NiTi and TC4. The study indicates that the interlayers promote melt nucleus growth and influence its morphology. The melt nucleus in Ni-containing joints exhibits an “M”-shaped morphology, while those in Cu- or Nb-containing joints are elliptical. Research reveals the presence of Intermetallic compounds (IMCs) between the direct weld and Ni-containing joints, which are the primary factor affecting joint strength. Joint mechanical properties initially increased then decreased with rising welding current. At I = 7 kA, the Cu-containing joint achieved maximum mechanical properties, fracture energy, and fusion diameter: tensile load 7.28 kN, fracture energy 6.62 J, and fusion diameter 3556 μm. No significant stress concentration was observed, consistent with simulation results. All joints exhibited interfacial failure. The fracture mode for the Cu-containing joint was ductile fracture; the Nb-containing joint showed a mixed ductile-brittle fracture; while the direct weld and Ni-containing joints exhibited brittle fracture.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"191 ","pages":"Article 109179"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185336","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}

引用次数: 0

Phase stability and coarsening mechanism in AlCrFeNi3 eutectic medium-entropy alloy during prolonged isothermal annealing AlCrFeNi3共晶中熵合金长时间等温退火过程中的相稳定性及粗化机制

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-02-09 DOI: 10.1016/j.intermet.2026.109199

Yong Dong , Wenxuan Li , Shougang Duan , Huiting Zheng

This study systematically investigates the effects of prolonged isothermal annealing (up to 400 h) at medium (700 °C) and high (1000 °C) temperatures on the microstructural evolution and mechanical properties of an as-cast AlCrFeNi₃ eutectic medium-entropy alloy (EMEA). The results revealed that the lamellar structure becomes unstable at 1000 °C, leading to the fragmentation and spheroidization of the B2 phase, accompanied by the formation of fine spherical B2 precipitates due to Al enrichment. In contrast, the lamellar structure remains largely stable at 700 °C, with only discontinuous coarsening observed at some eutectic cell boundaries after extended holding. The nanoscale L1₂ precipitates within the FCC phase coarsen into elongated shapes at 700 °C, while they refine at 1000 °C. Concurrently, the Cr-rich BCC precipitates within the B2 phase dissolve at 1000 °C but continue to grow at 700 °C. Notably, significant Cr segregation at the B2/FCC phase interfaces at 700 °C leads to the formation of irregular, coarse Cr-rich BCC precipitates, which are considerably larger than those in the interior of the B2 phase. The microstructural changes directly govern the mechanical properties. Annealing at 1000 °C enhances ductility at the expense of a slight reduction in strength. Conversely, treatment at 700 °C significantly increases yield strength but sacrifices ductility. A two-step annealing process (1000 °C/100 h followed by 700 °C/100 h) effectively enhances the strength with only a marginal decrease in ductility.

本研究系统地研究了中（700°C）和高温（1000°C）长时间等温退火（长达400 h）对铸态AlCrFeNi3共晶中熵合金（EMEA）显微组织演变和力学性能的影响。结果表明，在1000℃时，层状结构变得不稳定，导致B2相碎裂和球化，同时由于Al的富集而形成细小的球状B2析出相。相比之下，在700°C时，片层结构基本保持稳定，在延长保温时间后，仅在某些共晶细胞边界处观察到不连续的粗化。FCC相内的纳米级L12析出物在700℃时粗化成细长状，在1000℃时细化。同时，B2相中富cr的BCC析出物在1000℃时溶解，但在700℃时继续生长。值得注意的是，在700°C时，B2/FCC相界面处明显的Cr偏析导致形成不规则的、粗糙的富Cr BCC相，其体积比B2相内部大得多。微观组织的变化直接决定了材料的力学性能。在1000℃下退火可以提高延展性，但强度会略有降低。相反，700℃处理显著提高屈服强度，但牺牲延展性。两步退火工艺（1000°C/100 h，然后是700°C/100 h）有效地提高了强度，但延展性只略有下降。

{"title":"Phase stability and coarsening mechanism in AlCrFeNi3 eutectic medium-entropy alloy during prolonged isothermal annealing","authors":"Yong Dong , Wenxuan Li , Shougang Duan , Huiting Zheng","doi":"10.1016/j.intermet.2026.109199","DOIUrl":"10.1016/j.intermet.2026.109199","url":null,"abstract":"<div><div>This study systematically investigates the effects of prolonged isothermal annealing (up to 400 h) at medium (700 °C) and high (1000 °C) temperatures on the microstructural evolution and mechanical properties of an as-cast AlCrFeNi<sub>3</sub> eutectic medium-entropy alloy (EMEA). The results revealed that the lamellar structure becomes unstable at 1000 °C, leading to the fragmentation and spheroidization of the B2 phase, accompanied by the formation of fine spherical B2 precipitates due to Al enrichment. In contrast, the lamellar structure remains largely stable at 700 °C, with only discontinuous coarsening observed at some eutectic cell boundaries after extended holding. The nanoscale L1<sub>2</sub> precipitates within the FCC phase coarsen into elongated shapes at 700 °C, while they refine at 1000 °C. Concurrently, the Cr-rich BCC precipitates within the B2 phase dissolve at 1000 °C but continue to grow at 700 °C. Notably, significant Cr segregation at the B2/FCC phase interfaces at 700 °C leads to the formation of irregular, coarse Cr-rich BCC precipitates, which are considerably larger than those in the interior of the B2 phase. The microstructural changes directly govern the mechanical properties. Annealing at 1000 °C enhances ductility at the expense of a slight reduction in strength. Conversely, treatment at 700 °C significantly increases yield strength but sacrifices ductility. A two-step annealing process (1000 °C/100 h followed by 700 °C/100 h) effectively enhances the strength with only a marginal decrease in ductility.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"191 ","pages":"Article 109199"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185331","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}

引用次数: 0

Effects of Si Addition on the glass forming ability and properties of FeBPNbCr amorphous alloys 添加Si对FeBPNbCr非晶合金非晶形成能力和性能的影响

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-02-09 DOI: 10.1016/j.intermet.2026.109198

Chaolin Zhang , Qiang Li , Xueru Fan , Chuanming Sun , Zhenduo Wu , Lei Xie , Chuntao Chang

The influence of Si content on the glass-forming ability (GFA), soft magnetic properties, and mechanical behavior of Fe₇₇Si_xB_13-xP₇Nb₂Cr₁ (x = 0, 2, 4, 6, 8) amorphous alloys was systematically investigated. Pair distribution function (PDF) analysis revealed that moderate Si substitution (x = 2–4) enhances atomic-scale disorder and suppresses short-range order, thereby optimizing atomic packing frustration and improving both GFA and soft magnetic performance. In contrast, excessive Si (x ≥ 6) induces Fe–Si clustering and partial medium-range ordering, reducing structural homogeneity and deteriorating GFA. Consequently, the Fe₇₇Si₄B₉P₇Nb₂Cr₁ amorphous alloy exhibits the best comprehensive properties, with a critical diameter of 1.5 mm, a high saturation flux density (B_s) of 1.38 T, a low coercivity (H_c) of 1.3 A/m, and an effective permeability (μ_e) of 8000 at 1 kHz after annealing at 450 °C for 10 min. This alloy also shows excellent mechanical performance, with a yield strength of 3489 MPa and compressive plasticity of 1.7%. Moreover, this alloy demonstrates excellent corrosion resistance, with a self-corrosion potential (E_corr) of - 0.48 V and a self-corrosion current density of 1.04 × 10⁻⁵ A cm⁻² in 3.5 wt% NaCl solution. X-ray photoelectron spectroscopy (XPS) analysis showed that Si promotes the formation of a compact, multilayered passive film enriched in Fe₂O₃, Cr₂O₃, Nb₂O₅, and SiO₂ which significantly improves corrosion resistance by inhibiting active dissolution and enhancing film stability. Overall, the Fe₇₇Si₄B₉P₇Nb₂Cr₁ amorphous alloy demonstrates a superior combination of high GFA, enhanced magnetic and mechanical properties, and outstanding corrosion resistance, making it a promising candidate for advanced soft magnetic applications in harsh environments.

系统研究了Si含量对Fe77SixB13-xP7Nb2Cr1 （x = 0,2,4,6,8）非晶合金非晶形成能力（GFA）、软磁性能和力学行为的影响。对分布函数（PDF）分析表明，适度的Si取代（x = 2-4）增强了原子尺度的无序性，抑制了短程有序，从而优化了原子堆积挫折，提高了GFA和软磁性能。相反，过量的Si （x≥6）会导致Fe-Si聚集和部分中程有序，降低结构均匀性，恶化GFA。结果表明，经450℃退火10 min后，Fe77Si4B9P7Nb2Cr1非晶合金的临界直径为1.5 mm，饱和磁通密度（Bs）为1.38 T，矫顽力（Hc）为1.3 a /m， 1 kHz时有效磁导率（μe）为8000，综合性能最佳。该合金的屈服强度为3489 MPa，抗压塑性为1.7%，具有优异的力学性能。此外，该合金具有优异的耐腐蚀性，在3.5 wt% NaCl溶液中，自腐蚀电位（Ecorr）为- 0.48 V，自腐蚀电流密度为1.04 × 10−5 a cm−2。x射线光电子能谱（XPS）分析表明，Si促进形成致密的多层钝化膜，富含Fe2O3、Cr2O3、Nb2O5和SiO2，通过抑制活性溶解和增强膜的稳定性，显著提高了膜的耐蚀性。总体而言，Fe77Si4B9P7Nb2Cr1非晶合金具有高GFA，增强的磁性和机械性能以及出色的耐腐蚀性，使其成为恶劣环境下先进软磁应用的有希望的候选国。

{"title":"Effects of Si Addition on the glass forming ability and properties of FeBPNbCr amorphous alloys","authors":"Chaolin Zhang , Qiang Li , Xueru Fan , Chuanming Sun , Zhenduo Wu , Lei Xie , Chuntao Chang","doi":"10.1016/j.intermet.2026.109198","DOIUrl":"10.1016/j.intermet.2026.109198","url":null,"abstract":"<div><div>The influence of Si content on the glass-forming ability (GFA), soft magnetic properties, and mechanical behavior of Fe<sub>77</sub>Si<sub>x</sub>B<sub>13-x</sub>P<sub>7</sub>Nb<sub>2</sub>Cr<sub>1</sub> (x = 0, 2, 4, 6, 8) amorphous alloys was systematically investigated. Pair distribution function (PDF) analysis revealed that moderate Si substitution (x = 2–4) enhances atomic-scale disorder and suppresses short-range order, thereby optimizing atomic packing frustration and improving both GFA and soft magnetic performance. In contrast, excessive Si (x ≥ 6) induces Fe–Si clustering and partial medium-range ordering, reducing structural homogeneity and deteriorating GFA. Consequently, the Fe<sub>77</sub>Si<sub>4</sub>B<sub>9</sub>P<sub>7</sub>Nb<sub>2</sub>Cr<sub>1</sub> amorphous alloy exhibits the best comprehensive properties, with a critical diameter of 1.5 mm, a high saturation flux density (<em>B</em><sub>s</sub>) of 1.38 T, a low coercivity (<em>H</em><sub>c</sub>) of 1.3 A/m, and an effective permeability (<em>μ</em><sub>e</sub>) of 8000 at 1 kHz after annealing at 450 °C for 10 min. This alloy also shows excellent mechanical performance, with a yield strength of 3489 MPa and compressive plasticity of 1.7%. Moreover, this alloy demonstrates excellent corrosion resistance, with a self-corrosion potential (<em>E</em><sub>corr</sub>) of - 0.48 V and a self-corrosion current density of 1.04 × 10<sup>−5</sup> A cm<sup>−2</sup> in 3.5 wt% NaCl solution. X-ray photoelectron spectroscopy (XPS) analysis showed that Si promotes the formation of a compact, multilayered passive film enriched in Fe<sub>2</sub>O<sub>3</sub>, Cr<sub>2</sub>O<sub>3</sub>, Nb<sub>2</sub>O<sub>5</sub>, and SiO<sub>2</sub> which significantly improves corrosion resistance by inhibiting active dissolution and enhancing film stability. Overall, the Fe<sub>77</sub>Si<sub>4</sub>B<sub>9</sub>P<sub>7</sub>Nb<sub>2</sub>Cr<sub>1</sub> amorphous alloy demonstrates a superior combination of high GFA, enhanced magnetic and mechanical properties, and outstanding corrosion resistance, making it a promising candidate for advanced soft magnetic applications in harsh environments.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"191 ","pages":"Article 109198"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185413","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}

引用次数: 0

Microstructure evolution of metastable dual-phase high-entropy alloy Fe50Mn30Co10Cr10 under Taylor impact tests: Experiments and constitutive modeling 亚稳双相高熵合金Fe50Mn30Co10Cr10在Taylor冲击试验下的组织演变：实验与本构模型

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-02-11 DOI: 10.1016/j.intermet.2026.109194

L.X. Chen , J. Xu , Tao Yang , Y.H. Li , Y. Cai , X.F. Wang , L. Lu , S.N. Luo

In order to investigate microstructure evolution after severe plastic deformation and calibrate the constitutive model, Taylor impact experiments are conducted on the metastable dual-phase high-entropy alloy (HEA)

{Fe}_{50} {Mn}_{30} {Co}_{10} {Cr}_{10}

. Two kinds of HEA projectiles (short-cylinder: diameter 6 mm, length 6 mm or long-cylinder: diameter 12 mm, length 40 mm) are launched. Parameters of the Johnson-Cook Cowper–Symonds constitutive model are optimized via the long-cylinder Taylor impact experiments. After cylinder Taylor impact tests, deformation microstructures at different regions are characterized, and finite element modelings (FEMs) based on the modified constitutive model are conducted to interpret deformation mechanisms. The face-centered cubic (FCC) to hexagonal close-packed (HCP) phase transformation is predominant. The distribution of the equivalent plastic strain obtained from the FEM analysis indicates pronounced deformation gradient along the impact direction, consistent with the gradient microstructure of the postmortem sample. The higher equivalent plastic strain promotes more intense phase transformation and leads to higher grain boundary densities in both phases. Moreover, at high impact velocity, the reverse HCP to FCC phase transformation and

{111} 〈 112 〉

deformation twinning at the impact surface is activated, primarily due to the increase in stacking fault energy caused by impact temperature rise.

为了研究剧烈塑性变形后的微观组织演变规律，并对HEA合金Fe50Mn30Co10Cr10进行了Taylor冲击试验。发射两种HEA弹（短筒：直径6毫米，长6毫米或长筒：直径12毫米，长40毫米）。通过长圆柱Taylor冲击实验，对Johnson-Cook cooper - symonds本构模型参数进行了优化。在Taylor冲击试验后，对不同区域的变形组织进行了表征，并基于改进的本构模型进行了有限元建模，对变形机理进行了解释。以面心立方（FCC）到六方密堆积（HCP）相变为主。有限元分析得到的等效塑性应变分布表明，沿冲击方向有明显的变形梯度，与死后试样的梯度显微结构相一致。等效塑性应变越高，相变越剧烈，两相的晶界密度越高。在高冲击速度下，激活了冲击面反向HCP到FCC相变和{111}< 112 >变形孪晶，这主要是由于冲击温升导致层错能增加。

{"title":"Microstructure evolution of metastable dual-phase high-entropy alloy Fe50Mn30Co10Cr10 under Taylor impact tests: Experiments and constitutive modeling","authors":"L.X. Chen , J. Xu , Tao Yang , Y.H. Li , Y. Cai , X.F. Wang , L. Lu , S.N. Luo","doi":"10.1016/j.intermet.2026.109194","DOIUrl":"10.1016/j.intermet.2026.109194","url":null,"abstract":"<div><div>In order to investigate microstructure evolution after severe plastic deformation and calibrate the constitutive model, Taylor impact experiments are conducted on the metastable dual-phase high-entropy alloy (HEA) <span><math><mrow><msub><mrow><mi>Fe</mi></mrow><mrow><mn>50</mn></mrow></msub><msub><mrow><mi>Mn</mi></mrow><mrow><mn>30</mn></mrow></msub><msub><mrow><mi>Co</mi></mrow><mrow><mn>10</mn></mrow></msub><msub><mrow><mi>Cr</mi></mrow><mrow><mn>10</mn></mrow></msub></mrow></math></span>. Two kinds of HEA projectiles (short-cylinder: diameter 6 mm, length 6 mm or long-cylinder: diameter 12 mm, length 40 mm) are launched. Parameters of the Johnson-Cook Cowper–Symonds constitutive model are optimized via the long-cylinder Taylor impact experiments. After cylinder Taylor impact tests, deformation microstructures at different regions are characterized, and finite element modelings (FEMs) based on the modified constitutive model are conducted to interpret deformation mechanisms. The face-centered cubic (FCC) to hexagonal close-packed (HCP) phase transformation is predominant. The distribution of the equivalent plastic strain obtained from the FEM analysis indicates pronounced deformation gradient along the impact direction, consistent with the gradient microstructure of the postmortem sample. The higher equivalent plastic strain promotes more intense phase transformation and leads to higher grain boundary densities in both phases. Moreover, at high impact velocity, the reverse HCP to FCC phase transformation and <span><math><mrow><mrow><mo>{</mo><mn>111</mn><mo>}</mo></mrow><mrow><mo>〈</mo><mn>112</mn><mo>〉</mo></mrow></mrow></math></span> deformation twinning at the impact surface is activated, primarily due to the increase in stacking fault energy caused by impact temperature rise.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"191 ","pages":"Article 109194"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185409","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}

引用次数: 0

Effects of laser thermal input on the magneto-impedance and stress-impedance behavior of Co-based amorphous ribbons 激光热输入对钴基非晶带磁阻抗和应力阻抗行为的影响

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-02-09 DOI: 10.1016/j.intermet.2026.109197

Yaqian Yang , Yunfei Wang , Yunlong Li, Tangfeng Feng, Faxiang Qin

The microstructural and magnetic transport properties of amorphous materials can be modified by laser-induced thermal input. Although laser cutting of amorphous ribbons has been previously reported, existing studies mainly focus on morphology, phase evolution, or static magnetic properties, and lack a systematic understanding of how thermal input regulates magnetoimpedance-related responses and their underlying mechanisms. We establish a direct causal link between side-selective laser thermal input, microstructural evolution, and the magnetoimpedance (MI) and stress-impedance (SI) behavior of Co_67.5Fe₄Mo_3.5Si₁₄B₉Cu₂ ribbons. By independently varying the irradiation side and scanning speed, the distinct effects of oxidation and residual stress relaxation near the ribbon edge are decoupled. Laser irradiation from the contact side (R-CS) facilitates stress relaxation and partial structural recovery, enhancing magnetic softness and yielding a maximum MI ratio of 437.7 %. In contrast, irradiation from the free surface (R-FS) induces excessive oxidation and magnetic discontinuity, significantly suppressing impedance sensitivity. The optimized contact-side-irradiated sample (R-CS-25) exhibits a high strain sensitivity (∼27.1) and a wide linear sensing range (∼4000 με). Mechanistically, tensile strain modulates the effective anisotropy field through magnetoelastic coupling, shifting the natural ferromagnetic resonance and enabling bias-free stress sensing. These results provide insights into the thermal-input-controlled tuning of magnetoelastic responses of Co-based amorphous ribbon and suggest a potential approach for designing high-performance MI and bias-free magnetoelastic sensors.

激光诱导的热输入可以改变非晶材料的微观结构和磁输运特性。虽然以前有关于激光切割非晶带的报道，但现有的研究主要集中在形貌，相演变或静态磁性能上，缺乏对热输入如何调节磁阻抗相关响应及其潜在机制的系统理解。我们建立了侧面选择性激光热输入、微观结构演变和Co67.5Fe4Mo3.5Si14B9Cu2带的磁阻抗（MI）和应力阻抗（SI）行为之间的直接因果关系。通过独立地改变辐照方向和扫描速度，可以将条带边缘附近的氧化和残余应力松弛的明显影响解耦。接触侧（R-CS）的激光照射促进了应力松弛和部分结构恢复，增强了磁性柔软度，最大MI比为437.7%。相反，来自自由表面（R-FS）的辐照会引起过度氧化和磁性不连续，显著抑制阻抗灵敏度。优化后的接触侧辐照样品（R-CS-25）具有高应变灵敏度（~ 27.1）和宽线性传感范围（~ 4000 με）。在机械上，拉伸应变通过磁弹性耦合调节有效的各向异性场，改变天然铁磁共振，实现无偏应力传感。这些结果为co基非晶带的磁弹性响应的热输入控制调谐提供了见解，并为设计高性能MI和无偏置磁弹性传感器提供了潜在的方法。

{"title":"Effects of laser thermal input on the magneto-impedance and stress-impedance behavior of Co-based amorphous ribbons","authors":"Yaqian Yang , Yunfei Wang , Yunlong Li, Tangfeng Feng, Faxiang Qin","doi":"10.1016/j.intermet.2026.109197","DOIUrl":"10.1016/j.intermet.2026.109197","url":null,"abstract":"<div><div>The microstructural and magnetic transport properties of amorphous materials can be modified by laser-induced thermal input. Although laser cutting of amorphous ribbons has been previously reported, existing studies mainly focus on morphology, phase evolution, or static magnetic properties, and lack a systematic understanding of how thermal input regulates magnetoimpedance-related responses and their underlying mechanisms. We establish a direct causal link between side-selective laser thermal input, microstructural evolution, and the magnetoimpedance (MI) and stress-impedance (SI) behavior of Co<sub>67.5</sub>Fe<sub>4</sub>Mo<sub>3.5</sub>Si<sub>14</sub>B<sub>9</sub>Cu<sub>2</sub> ribbons. By independently varying the irradiation side and scanning speed, the distinct effects of oxidation and residual stress relaxation near the ribbon edge are decoupled. Laser irradiation from the contact side (R-CS) facilitates stress relaxation and partial structural recovery, enhancing magnetic softness and yielding a maximum MI ratio of 437.7 %. In contrast, irradiation from the free surface (R-FS) induces excessive oxidation and magnetic discontinuity, significantly suppressing impedance sensitivity. The optimized contact-side-irradiated sample (R-CS-25) exhibits a high strain sensitivity (∼27.1) and a wide linear sensing range (∼4000 με). Mechanistically, tensile strain modulates the effective anisotropy field through magnetoelastic coupling, shifting the natural ferromagnetic resonance and enabling bias-free stress sensing. These results provide insights into the thermal-input-controlled tuning of magnetoelastic responses of Co-based amorphous ribbon and suggest a potential approach for designing high-performance MI and bias-free magnetoelastic sensors.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"191 ","pages":"Article 109197"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185329","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}

引用次数: 0

Phase stability and mechanical properties of novel metastable Ti-Zr-Ta medium entropy alloys with low elastic modulus for biomedical applications 新型低弹性模量亚稳Ti-Zr-Ta中熵合金的相稳定性和力学性能

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-02-11 DOI: 10.1016/j.intermet.2026.109207

Shiwen Hu , Pengjie Wei , Zefeng Chen , Wenxu Wang , Xinquan Shang , Dexue Liu

In recent years, Ti-based high- and medium-entropy alloys (H/MEAs) have attracted considerable attention as orthopedic implant materials due to their high strength and excellent biocompatibility. In this study, the phase stability and mechanical properties of (TiZr)_100-xTa_x (x = 10, 7, and 5, in molar ratio) MEAs, hereafter referred to as Ta5, Ta7, and Ta10 alloys, were investigated. The results show that as the Ta content decreases, the phase composition changes from β+α'' phase of Ta10 to α'' +α'+β phase of Ta7, and finally to α'+α''+β phase of Ta5, among which the phase with higher content is in the front. Driven by phase transformation activation and the regulation of the primary microstructure, the alloy strength decreased from 501 MPa to 399 MPa, then rebounded to 449 MPa. The elastic modulus of the alloy ranged from 53 to 65 GPa, significantly lower than that of Ti6Al4V, and was mainly regulated by phase composition and content. With increasing tensile strain, the β phase in the alloy underwent a martensitic transformation, β→α''. Simultaneously, some α′ phases gradually transformed into α'' phases. Both fractured Ta5 and Ta7 alloys possessed an α'' matrix and were rich in α′ shear bands. In particular, the Ta10 alloy exhibited a uniform and random distribution of the α′ phase within its α'' matrix. Furthermore, this matrix was also rich in α′ and β shear bands.

近年来，ti基高、中熵合金（H/MEAs）因其高强度和优异的生物相容性而成为骨科植入材料的研究热点。本文研究了（TiZr）100-xTax （x = 10、7和5，摩尔比）MEAs（以下简称Ta5、Ta7和Ta10合金）的相稳定性和力学性能。结果表明：随着Ta含量的降低，Ta10的相组成由β+α “相转变为Ta7的α ” +α'+β相，最后变为Ta5的α'+α " +β相，其中Ta含量较高的相处于最前面；在相变激活和初生组织调控的作用下，合金强度由501 MPa降至399 MPa，而后反弹至449 MPa。合金的弹性模量在53 ~ 65 GPa之间，明显低于Ti6Al4V合金，其弹性模量主要受相组成和含量的调控。随着拉伸应变的增大，合金中的β相发生马氏体相变，β→α”。同时，部分α′相逐渐转变为α′相。断裂的Ta5和Ta7合金均以α”为基体，具有丰富的α’剪切带。Ta10合金的α′相在其α′基体中表现出均匀而随机的分布。此外，该基质还含有丰富的α′和β剪切带。

{"title":"Phase stability and mechanical properties of novel metastable Ti-Zr-Ta medium entropy alloys with low elastic modulus for biomedical applications","authors":"Shiwen Hu , Pengjie Wei , Zefeng Chen , Wenxu Wang , Xinquan Shang , Dexue Liu","doi":"10.1016/j.intermet.2026.109207","DOIUrl":"10.1016/j.intermet.2026.109207","url":null,"abstract":"<div><div>In recent years, Ti-based high- and medium-entropy alloys (H/MEAs) have attracted considerable attention as orthopedic implant materials due to their high strength and excellent biocompatibility. In this study, the phase stability and mechanical properties of (TiZr)<sub>100-x</sub>Ta<sub>x</sub> (x = 10, 7, and 5, in molar ratio) MEAs, hereafter referred to as Ta5, Ta7, and Ta10 alloys, were investigated. The results show that as the Ta content decreases, the phase composition changes from β+α'' phase of Ta10 to α'' +α'+β phase of Ta7, and finally to α'+α''+β phase of Ta5, among which the phase with higher content is in the front. Driven by phase transformation activation and the regulation of the primary microstructure, the alloy strength decreased from 501 MPa to 399 MPa, then rebounded to 449 MPa. The elastic modulus of the alloy ranged from 53 to 65 GPa, significantly lower than that of Ti6Al4V, and was mainly regulated by phase composition and content. With increasing tensile strain, the β phase in the alloy underwent a martensitic transformation, β→α''. Simultaneously, some α′ phases gradually transformed into α'' phases. Both fractured Ta5 and Ta7 alloys possessed an α'' matrix and were rich in α′ shear bands. In particular, the Ta10 alloy exhibited a uniform and random distribution of the α′ phase within its α'' matrix. Furthermore, this matrix was also rich in α′ and β shear bands.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"191 ","pages":"Article 109207"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185328","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}

引用次数: 0

Effects of minor Cu content addition on mechanical properties of Co-Ta-B-Si bulk metallic glasses 微量Cu对Co-Ta-B-Si块体金属玻璃力学性能的影响

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-02-05 DOI: 10.1016/j.intermet.2026.109192

Qiang Huang , Yanhua Chen , Shuyan Zhang , Xingxing Bai , Min Shi , Jiankang Ye , Miaomiao Lv , Yiran Zhang

In this study, induction melting combined with J-quenching technique was used to prepare (Co_0.63Ta_0.1B_0.25Si_0.02)_100-xCu_x (x = 0–0.9 at.%) Co-based bulk metallic glasses were systematically probed for the effects of trace Cu doping on the modulation of its mechanical properties and deformation mechanism. The results show that when the Cu content is 0.3–0.5 at.%, the comprehensive properties of the alloys are significantly enhanced. The material obtains optimal plastic deformation capacity at x = 0.5, with a compressive fracture strength of 5500 MPa and an increase in plastic strain up to 5.5 %. Meanwhile, the critical diameter (D_c) can reach 2 mm for Cu_0.5 sample, and the supercooled liquid region (ΔT_x) broadens to the maximum value of 46.9 K, suggesting the glass formation ability (GFA) is properly enhanced with the minor addition of Cu. Microscopic mechanism studies show that the positive mixing enthalpy of Cu - Co atoms induces the formation of short-range ordered nanoclusters at 1–2 nm scale (cluster density reaches 18 % at x = 0.5), which contributes to the free volume distribution and the multiplicity of high-density shear bands to proliferate. Serrated flow behavior analysis reveals that Cu doping decreases the critical shear band velocity (CSBV) to 5.09 × 10⁻⁶ m/s, and statistical analysis of the sawtooth stress drop transformed from Gaussian to power law distribution, indicating the enhancement of shear band interactions and the deceleration of propagation. This synergistic effect enhances the plasticity by modulating the self-organized behavior of the shear band, while the excess Cu (x > 0.5) leads to the performance deterioration due to the structural instability. This study provides a theoretical basis for the design of new Co-based metallic glasses with both ultra-high strength and moderate plasticity.

本研究采用感应熔炼结合j -淬火技术制备了（Co0.63Ta0.1B0.25Si0.02）100-xCux （x = 0-0.9 at）。系统地探讨了微量Cu掺杂对co基大块金属玻璃力学性能和变形机理的影响。结果表明，当Cu含量为0.3 ~ 0.5 at时。%，合金的综合性能显著提高。该材料在x = 0.5时获得最佳塑性变形能力，抗压断裂强度为5500 MPa，塑性应变增加5.5%。同时，Cu0.5样品的临界直径（Dc）可达2 mm，过冷液区（ΔTx）扩大至最大值46.9 K，表明少量Cu的加入可适当增强玻璃形成能力（GFA）。微观机理研究表明，Cu - Co原子的正混合焓诱导了1 ~ 2 nm尺度上的短程有序纳米团簇的形成（x = 0.5时团簇密度达到18%），这有助于自由体积分布和高密度剪切带的多重增殖。锯齿状流动行为分析表明，Cu掺杂使临界剪切带速度（CSBV）降低至5.09 × 10−6 m/s，锯齿形应力降由高斯分布转变为幂律分布，表明剪切带相互作用增强，传播减速。这种协同效应通过调节剪切带的自组织行为来增强塑性，而过量的Cu （x > 0.5）会导致结构失稳而导致性能下降。本研究为设计超高强度和中等塑性的新型钴基金属玻璃提供了理论依据。

{"title":"Effects of minor Cu content addition on mechanical properties of Co-Ta-B-Si bulk metallic glasses","authors":"Qiang Huang , Yanhua Chen , Shuyan Zhang , Xingxing Bai , Min Shi , Jiankang Ye , Miaomiao Lv , Yiran Zhang","doi":"10.1016/j.intermet.2026.109192","DOIUrl":"10.1016/j.intermet.2026.109192","url":null,"abstract":"<div><div>In this study, induction melting combined with J-quenching technique was used to prepare (Co<sub>0.63</sub>Ta<sub>0.1</sub>B<sub>0.25</sub>Si<sub>0.02</sub>)<sub>100-x</sub>Cu<sub>x</sub> (x = 0–0.9 at.%) Co-based bulk metallic glasses were systematically probed for the effects of trace Cu doping on the modulation of its mechanical properties and deformation mechanism. The results show that when the Cu content is 0.3–0.5 at.%, the comprehensive properties of the alloys are significantly enhanced. The material obtains optimal plastic deformation capacity at x = 0.5, with a compressive fracture strength of 5500 MPa and an increase in plastic strain up to 5.5 %. Meanwhile, the critical diameter (<em>D</em><sub>c</sub>) can reach 2 mm for Cu<sub>0.5</sub> sample, and the supercooled liquid region (Δ<em>T</em><sub>x</sub>) broadens to the maximum value of 46.9 K, suggesting the glass formation ability (GFA) is properly enhanced with the minor addition of Cu. Microscopic mechanism studies show that the positive mixing enthalpy of Cu - Co atoms induces the formation of short-range ordered nanoclusters at 1–2 nm scale (cluster density reaches 18 % at x = 0.5), which contributes to the free volume distribution and the multiplicity of high-density shear bands to proliferate. Serrated flow behavior analysis reveals that Cu doping decreases the critical shear band velocity (CSBV) to 5.09 × 10<sup>−6</sup> m/s, and statistical analysis of the sawtooth stress drop transformed from Gaussian to power law distribution, indicating the enhancement of shear band interactions and the deceleration of propagation. This synergistic effect enhances the plasticity by modulating the self-organized behavior of the shear band, while the excess Cu (x > 0.5) leads to the performance deterioration due to the structural instability. This study provides a theoretical basis for the design of new Co-based metallic glasses with both ultra-high strength and moderate plasticity.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"191 ","pages":"Article 109192"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146185340","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}

引用次数: 0

Gas tungsten arc welding of NiTi shape memory alloy and AlCoCrFeNi2.1 eutectic high entropy alloy using a niobium interlayer 采用铌中间层对NiTi形状记忆合金和AlCoCrFeNi2.1共晶高熵合金进行钨极气体保护焊

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-01-28 DOI: 10.1016/j.intermet.2026.109177

Nithin Joseph Reddy Sagili Arthur , Rae Eon Kim , Ana Martins , Hyoung Seop Kim , N. Schell , João Pedro Oliveira

Dissimilar fusion welding of a NiTi shape memory alloy and an AlCoCrFeNi_2.1 eutectic high entropy alloy was performed using a niobium interlayer. The unique properties of these materials complement each other, potentially enabling hybrid structures for advanced applications and smart systems. Gas tungsten arc welding with an arc offset technique was employed to create a weld-braze joint at the NiTi-Nb interface while controlling the heat input. Comprehensive microstructural and phase analysis was carried out using optical and electron microscopy, synchrotron X-ray diffraction, and was further supplemented by thermodynamic simulations. Dissolution of the Nb interlayer altered the solidification pathways in the fusion zone, leading to the formation of topologically close-packed phases (including C14 Laves and σ) and Ti₂Ni. Multiple interfacial reactions at the NiTi interface introduced significant strain, which increased hardness but also acted as stress concentrators during tensile loading. The addition of the niobium interlayer enabled the formation of a stable, crack-free joint, whereas welding without an interlayer resulted in catastrophic cracking.

采用铌夹层对NiTi形状记忆合金和AlCoCrFeNi2.1共晶高熵合金进行了异种熔焊。这些材料的独特特性相互补充，有可能为先进应用和智能系统提供混合结构。在控制热输入的情况下，采用电弧偏移技术的钨气弧焊在NiTi-Nb界面处形成钎焊接头。利用光学显微镜、电子显微镜、同步加速器x射线衍射进行了全面的显微组织和物相分析，并进一步辅以热力学模拟。Nb中间层的溶解改变了熔合区的凝固路径，形成了拓扑紧密堆积相（包括C14 Laves和σ）和Ti2Ni。NiTi界面上的多重界面反应产生了显著的应变，增加了硬度，但在拉伸加载过程中也起到了应力集中的作用。添加铌中间层可以形成稳定、无裂纹的接头，而不添加中间层的焊接会导致灾难性的开裂。

{"title":"Gas tungsten arc welding of NiTi shape memory alloy and AlCoCrFeNi2.1 eutectic high entropy alloy using a niobium interlayer","authors":"Nithin Joseph Reddy Sagili Arthur , Rae Eon Kim , Ana Martins , Hyoung Seop Kim , N. Schell , João Pedro Oliveira","doi":"10.1016/j.intermet.2026.109177","DOIUrl":"10.1016/j.intermet.2026.109177","url":null,"abstract":"<div><div>Dissimilar fusion welding of a NiTi shape memory alloy and an AlCoCrFeNi<sub>2.1</sub> eutectic high entropy alloy was performed using a niobium interlayer. The unique properties of these materials complement each other, potentially enabling hybrid structures for advanced applications and smart systems. Gas tungsten arc welding with an arc offset technique was employed to create a weld-braze joint at the NiTi-Nb interface while controlling the heat input. Comprehensive microstructural and phase analysis was carried out using optical and electron microscopy, synchrotron X-ray diffraction, and was further supplemented by thermodynamic simulations. Dissolution of the Nb interlayer altered the solidification pathways in the fusion zone, leading to the formation of topologically close-packed phases (including C14 Laves and σ) and Ti<sub>2</sub>Ni. Multiple interfacial reactions at the NiTi interface introduced significant strain, which increased hardness but also acted as stress concentrators during tensile loading. The addition of the niobium interlayer enabled the formation of a stable, crack-free joint, whereas welding without an interlayer resulted in catastrophic cracking.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"191 ","pages":"Article 109177"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146075911","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}

引用次数: 0

Unveiling the influence of Al/Ti ratio on microstructural evolution and creep behaviors in low-density Ni3Al-based SX superalloys 揭示了Al/Ti比对低密度ni3al基SX高温合金显微组织演变和蠕变行为的影响

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-01-23 DOI: 10.1016/j.intermet.2026.109174

Hang Cai , Zhitao Li , Yujun Sun , Tianren Qu , Qi Han , Yunsheng Wu , Xianjun Guan , Le Zhao , Jieshan Hou , Lan-zhang Zhou

The effect of various Al/Ti ratio on microstructural characteristics and creep behavior at 1100 °C/100 MPa in low-density Ni₃Al-based single crystal superalloys was systematically investigated through multi-technique characterization. Quantitative analysis revealed that a direct correlation between increasing Al/Ti ratios progressively adjusted from 0.54 through 1.00 to 1.86 and corresponding enhancement in γ′ phase volume fraction from 67.9 % to 75.6 % and ultimately 80.4 %. This compositional modification concurrently induces three critical microstructural transformations: first, refinement of γ′ precipitates into cubic morphology with the shape factors closer to 1.41; second, narrowing of γ channels from 96.5 nm to 56.0 nm and then to 45.6 nm; third, preferential partitioning of large-radius elements including Cr and W into γ phases, driving γ/γ′ lattice misfit towards increased negative values from −0.127 % to −0.185 % and finally −0.350 %. Contrary to conventional Ti-dominated γ′ paradigm, the results in this study demonstrated superior creep performance in higher Al/Ti ratio alloys. A variety of strengthening mechanisms related to microstructures are analyzed, and the results reveal that, enhanced solid-solution strengthening in the γ phase arises from Al/Ti ratio-controlled partitioning of Mo, W and Cr solutes. Finer γ′ precipitate, higher γ′ volume fraction and narrow γ channel width induced by increasing Al/Ti ratio collectively elevate the threshold stress for dislocation climb from 24 MPa to 86 MPa. Additionally, a well-developed rafting of γ′ phase was observed in higher Al/Ti ratio alloy after creep, which also plays a role in reducing the creep rate. Finally, more completed and denser dislocations network are located at the γ/γ′ interface in the higher Al/Ti ratio alloy, effectively impeding dislocation from cutting into the γ′ precipitates, thereby reducing the minimum creep rate from 1.46 × 10⁻⁵ %‧s⁻¹ to 1.25 × 10⁻⁶ %‧s⁻¹, and the creep life extension up to 138.08 h. This performance represents a significant improvement over reported values for low-density superalloys.

通过多技术表征，系统研究了不同Al/Ti比对低密度ni3al基单晶高温合金1100℃/100 MPa下显微组织特征和蠕变行为的影响。定量分析表明，Al/Ti比值从0.54→1.00→1.86的增加与γ′相体积分数从67.9%→75.6%→80.4%的增加直接相关。这种成分改性同时引发了三个关键的微观组织转变：首先，γ′析出相细化为立方形态，形状因子接近1.41；第二，γ通道从96.5 nm缩小到56.0 nm，再缩小到45.6 nm；第三，Cr和W等大半径元素优先划分为γ相，导致γ/γ′晶格错配值从- 0.127%增加到- 0.185%，最终增加到- 0.350%。与传统的以Ti为主的γ′模式相反，本研究的结果表明，高Al/Ti比的合金具有优越的蠕变性能。分析了与显微组织相关的多种强化机制，结果表明，γ相的固溶强化是由Al/Ti比例控制的Mo、W和Cr溶质分配引起的。随着Al/Ti比的增大，γ′析出物的细化、γ′体积分数的增大和γ通道宽度的减小，使位错爬升的阈值应力从24 MPa提高到86 MPa。此外，在高Al/Ti比合金中，蠕变后γ′相有较发达的漂流，这也对降低蠕变速率起作用。最后，高Al/Ti比合金在γ/γ′界面处形成了更完整、更密集的位错网络，有效地阻止位错进入γ′析出相，从而使最小蠕变速率从1.46 × 10 - 5%·s−1降低到1.25 × 10 - 6%·s−1，蠕变寿命延长至138.08 h。这一性能比报道的低密度高温合金的数值有了显著提高。

{"title":"Unveiling the influence of Al/Ti ratio on microstructural evolution and creep behaviors in low-density Ni3Al-based SX superalloys","authors":"Hang Cai , Zhitao Li , Yujun Sun , Tianren Qu , Qi Han , Yunsheng Wu , Xianjun Guan , Le Zhao , Jieshan Hou , Lan-zhang Zhou","doi":"10.1016/j.intermet.2026.109174","DOIUrl":"10.1016/j.intermet.2026.109174","url":null,"abstract":"<div><div>The effect of various Al/Ti ratio on microstructural characteristics and creep behavior at 1100 °C/100 MPa in low-density Ni<sub>3</sub>Al-based single crystal superalloys was systematically investigated through multi-technique characterization. Quantitative analysis revealed that a direct correlation between increasing Al/Ti ratios progressively adjusted from 0.54 through 1.00 to 1.86 and corresponding enhancement in γ′ phase volume fraction from 67.9 % to 75.6 % and ultimately 80.4 %. This compositional modification concurrently induces three critical microstructural transformations: first, refinement of γ′ precipitates into cubic morphology with the shape factors closer to 1.41; second, narrowing of γ channels from 96.5 nm to 56.0 nm and then to 45.6 nm; third, preferential partitioning of large-radius elements including Cr and W into γ phases, driving γ/γ′ lattice misfit towards increased negative values from −0.127 % to −0.185 % and finally −0.350 %. Contrary to conventional Ti-dominated γ′ paradigm, the results in this study demonstrated superior creep performance in higher Al/Ti ratio alloys. A variety of strengthening mechanisms related to microstructures are analyzed, and the results reveal that, enhanced solid-solution strengthening in the γ phase arises from Al/Ti ratio-controlled partitioning of Mo, W and Cr solutes. Finer γ′ precipitate, higher γ′ volume fraction and narrow γ channel width induced by increasing Al/Ti ratio collectively elevate the threshold stress for dislocation climb from 24 MPa to 86 MPa. Additionally, a well-developed rafting of γ′ phase was observed in higher Al/Ti ratio alloy after creep, which also plays a role in reducing the creep rate. Finally, more completed and denser dislocations network are located at the γ/γ′ interface in the higher Al/Ti ratio alloy, effectively impeding dislocation from cutting into the γ′ precipitates, thereby reducing the minimum creep rate from 1.46 × 10<sup>−5</sup> %‧s<sup>−1</sup> to 1.25 × 10<sup>−6</sup> %‧s<sup>−1</sup>, and the creep life extension up to 138.08 h. This performance represents a significant improvement over reported values for low-density superalloys.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"191 ","pages":"Article 109174"},"PeriodicalIF":4.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146015847","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}

引用次数: 0

Unexpected carbide formation in the FeCoNiCr high-entropy alloy under prolonged high temperature ion irradiation FeCoNiCr高熵合金在长时间高温离子辐照下意外形成碳化物

IF 4.8 2区材料科学 Q2 CHEMISTRY, PHYSICAL

Intermetallics

Pub Date : 2026-04-01 Epub Date: 2026-02-02 DOI: 10.1016/j.intermet.2026.109193

Da Chen , Yingming Sang , Zhaoyi Cheng , Jianrong Sun , Shaofei Liu , Guma Yeli , Ji-Jung Kai

In this study, the solid solution FeCoNiCr high-entropy alloy (HEA) was heavily irradiated by 3 MeV Ni ions to ∼ 107 dpa at 873 K. Transmission electron microscopy characterizations revealed that the multicomponent carbides of M₂₃C₆ (M = Cr, Fe, Co, Ni) formed at a specific depth range adjacent to the peak radiation damage layer. The grain boundaries were more sensitive to precipitation where the carbides showed a larger size, denser distribution and higher Cr-concentration. For the underlying mechanisms, carbon contaminations from irradiation chamber were believed to introduce C which diffused into the alloy during high-temperature irradiation. Meanwhile, the radiation induced supersaturation of Cr-interstitials supplied the necessary solutes for precipitation. The kinetic stability of carbides was controlled by radiation cascade damage against the thermodynamic driving force for phase formation. It explains why precipitates appeared at a defined depth.

在本研究中，采用3mev Ni离子在873 K下重照射FeCoNiCr高熵合金（HEA）至~ 107 dpa。透射电镜表征表明，M23C6的多组分碳化物（M = Cr, Fe, Co, Ni）在峰值辐射损伤层附近的特定深度范围内形成。晶界对析出更敏感，碳化物尺寸更大，分布更密，cr浓度更高。在高温辐照过程中，辐照室的碳污染将C引入合金，并扩散到合金中。同时，辐射诱导的cr间隙过饱和为沉淀提供了必要的溶质。碳化物的动力学稳定性是由相形成的热力学驱动力的辐射级联损伤控制的。它解释了为什么沉淀出现在一定的深度。

引用次数: 0