Vacuum最新文献 - Book学术

Promoting strength-ductility synergy by heterogeneous grain structure in a zirconium-alloyed Fe-Mn-Al-C low-density steel 锆合金Fe-Mn-Al-C低密度钢的非均相组织促进强度-塑性协同作用

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-16 DOI: 10.1016/j.vacuum.2026.115094

Yuheng Wang, Runze Yu, Fengchao An, Suotao Wang, Hao Wang, Zibo Zhao, Hongpu Yue, Tianxiang Gao, Junting Luo, Junsong Zhang, Riping Liu

Heterostructures, particularly dual-phase heterostructures, often lead to hetero-interfacial stress concentration, and ultimately premature failure, though they benefit from heterogeneous deformation. Addressing the challenge of strain localization and hetero-interfacial cracking, a single-phase heterogeneous grain structure is designed through tuning zirconium (Zr) content and employing precise thermo-mechanical treatment. As Zr content increases to 0.50 wt %, a single-phase bimodal grain structure is successfully engineered, including soft coarse grain zones (∼5 μm in size and 65 % in area) and hard fine grain zones (∼1 μm in size and 35 % in area). Such bimodal heterostructure is mainly ascribed to the retarding effect of recrystallization, due to the drag effect of Zr atoms and Zener pinning of ZrC. The synergistic effects of microstructural heterogeneity and ZrC precipitation enhance the strengths. Furthermore, multistage deformation mechanisms, involving heterogeneous deformation-induced hardening, dislocation slip and nanotwinning, enable the strain hardening capability and ductility.

异质结构，特别是双相异质结构，通常会导致异质界面应力集中，最终导致过早破坏，尽管它们受益于非均质变形。针对应变局部化和异质界面开裂的难题，通过调整锆（Zr）含量和采用精密热处理，设计了单相非均质晶粒结构。当Zr含量增加到0.50 wt %时，成功地设计了单相双峰晶结构，包括软粗晶区（尺寸~ 5 μm，面积65%）和硬细晶区（尺寸~ 1 μm，面积35%）。这种双峰异质结构主要是由于Zr原子的阻力作用和ZrC的齐纳钉扎作用对再结晶的阻碍作用。微观组织非均质性和ZrC析出的协同作用增强了材料的强度。此外，非均匀变形诱发硬化、位错滑移和纳米孪晶等多阶段变形机制使材料具有应变硬化能力和延性。

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引用次数: 0

Study on the rare earth phases, crystal textures and mechanical properties of pulsed laser welded Mg-5Al-2Gd-0.5Mn alloy weld 脉冲激光焊接Mg-5Al-2Gd-0.5Mn合金焊缝稀土相、晶构及力学性能研究

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-16 DOI: 10.1016/j.vacuum.2026.115099

Bangfu Zhang , Xiaobin Zhang , Pengfei Zhao , Shuwang Bian , Kanglin Ke , Weifeng Xie

Due to the relatively low strength and plasticity of magnesium alloy welding joints, RE elements can enhance the strength and plasticity of magnesium alloys. Based on this, a rolled-state Mg-5Al-2Gd-0.5Mn rare earth magnesium alloy was developed and welded using pulsed laser welding technology. The research results indicate that the tensile strength reaches as high as 263.5 MPa, the fracture type is ductile fracture. Inside the grains, the main phase is the sub - micron - sized Al₂Gd phase. Near the grain boundaries, it is mainly the nano - sized Al₈Mn₄Gd phase, and at the grain boundaries, both phases coexist. During the growth process of the rare – earth (RE) phases, the intra - granular RE phases act as heterogeneous nucleation sites, and the grain - boundary RE phases absorb the Mg₁₇Al₁₂ phase to form a polycrystalline phase at the grain boundaries. Their combined effect refines the grains. After forming, the intra - granular RE phases connect to form a strong pinning effect, which hinders the dislocation slip and shares more stress for the matrix. Meanwhile, the RE phases at the grain boundaries reduce the segregation of impurities and strengthen the grain boundaries.

由于镁合金焊接接头强度和塑性相对较低，稀土元素可以提高镁合金的强度和塑性。在此基础上，研制了轧制态Mg-5Al-2Gd-0.5Mn稀土镁合金，并采用脉冲激光焊接技术进行焊接。研究结果表明，拉伸强度高达263.5 MPa，断裂类型为韧性断裂。晶粒内部的主要相为亚微米大小的Al2Gd相。在晶界处主要为纳米Al8Mn4Gd相，在晶界处两相并存。在稀土相生长过程中，晶内稀土相作为非均相成核位点，晶界稀土相吸收Mg17Al12相，在晶界处形成多晶相。它们的共同作用使晶粒更加精细。形成后，颗粒内稀土相相互连接，形成较强的钉住作用，阻碍了位错滑移，为基体分担了较大的应力。同时，晶界处的稀土相减少了杂质的偏析，强化了晶界。

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引用次数: 0

First-principles study of efficient solid-state hydrogen storage materials XSc3H8 (X = Rb and Cs) 高效固态储氢材料XSc3H8 （X = Rb和Cs）的第一性原理研究

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-14 DOI: 10.1016/j.vacuum.2026.115088

Ziyan Dai , Saifei Wang , Xueli Xiang , Yan Chen , Shanjun Chen , Weibin Zhang

The structural, mechanical, hydrogen storage, optical, electronic, dynamic, and thermodynamic characteristics of XSc₃H₈ (X = Rb and Cs) compounds are investigated via first-principles calculations. The negative formation energies of RbSc₃H₈ (−0.55 eV/atom) and CsSc₃H₈ (−0.46 eV/atom) confirm their thermodynamic stability. The absence of imaginary frequencies in the phonon spectra verifies the dynamic stability of both compounds. The mechanical stability of RbSc₃H₈ and CsSc₃H₈ is validated by the elastic constants that meet the Born stability criteria. RbSc₃H₈ and CsSc₃H₈ exhibit gravimetric hydrogen storage capacities of 3.53 wt% and 2.92 wt%, respectively. The hydrogen desorption temperatures are 402.80 K for RbSc₃H₈ and 339.01 K for CsSc₃H₈, which are suitable for H₂ desorption. The mechanical properties indicate that RbSc₃H₈ exhibits brittle characteristics, whereas CsSc₃H₈ displays ductility, and both materials exhibit anisotropic characteristics. The analysis of electronic band structures reveals that these hydrides display metallic properties. Their optical characteristics indicate that they are materials with high polarizability. Our research suggests that RbSc₃H₈ exhibits greater potential as a hydrogen storage material due to its superior gravimetric hydrogen storage capacity, making it particularly suitable for weight-sensitive applications such as mobile hydrogen storage. While CsSc₃H₈ offers advantages in low-temperature applications owing to its lower desorption temperature.

通过第一性原理计算研究了XSc3H8 （X = Rb和Cs）化合物的结构、力学、储氢、光学、电子、动力学和热力学特性。RbSc3H8 （- 0.55 eV/原子）和CsSc3H8 （- 0.46 eV/原子）的负形成能证实了它们的热力学稳定性。声子谱中不存在虚频率，证实了这两种化合物的动态稳定性。RbSc3H8和CsSc3H8的弹性常数满足Born稳定性准则，验证了它们的力学稳定性。RbSc3H8和CsSc3H8的重量储氢量分别为3.53 wt%和2.92 wt%。RbSc3H8的脱氢温度为402.80 K， CsSc3H8的脱氢温度为339.01 K。力学性能表明，RbSc3H8表现出脆性特征，CsSc3H8表现出延性特征，两种材料均表现出各向异性特征。电子能带结构分析表明，这些氢化物具有金属性质。它们的光学特性表明它们是具有高极化率的材料。我们的研究表明，RbSc3H8作为一种储氢材料表现出更大的潜力，因为它具有优越的重量储氢能力，使其特别适合于重量敏感的应用，如移动储氢。而CsSc3H8由于其较低的解吸温度，在低温应用中具有优势。

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引用次数: 0

Dynamic polarity switching under DC-biased AC waveforms: Mechanistic insights into hydroxyapatite coating via electrochemical deposition 直流偏置交流波形下的动态极性切换：通过电化学沉积对羟基磷灰石涂层的机理研究

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-13 DOI: 10.1016/j.vacuum.2026.115091

Kusuma Putri Suwondo , Muhammad Kozin , Rima Angellina , Yulia Elfena , Diah Ayu Fitriani , Agus Nugroho , Adita Wardani Rahmania , Erie Martides , Muhammad Prisla Kamil , Prabowo Puranto

Hydroxyapatite (HA) coatings enhance the biological integration and corrosion performance of titanium implants; however, conventional direct-current (DC) electrochemical deposition (ECD) often yields porous, weakly adherent layers. This study introduces a DC-biased alternating current (AC) ECD, by superimposing a 10 V sinusoidal waveform onto DC biases of 2.5, 5.0, and 7.5 V, to regulate HA growth on Ti-6Al-4V. Increasing the DC bias shifted the deposition regime, leading to a morphological evolution from short crystallites to elongated, interconnected needle-like networks. X-ray diffraction revealed sharpened HA reflections, indicating enhanced crystallinity, while surface roughness and hydrophilicity also increased. Potentiodynamic polarization demonstrated improved corrosion resistance, with 2.5 V_DC exhibit lowest j_corr of (3.17 ± 0.05) × 10⁻⁸ A cm⁻² and protection efficiencies of (91 ± 4) %. All coatings promoted secondary apatite formation in simulated body fluid. This approach provides a tunable, low-temperature pathway for engineering compact, corrosion-resistant HA layers.

羟基磷灰石（HA）涂层增强了钛种植体的生物整合和腐蚀性能；然而，传统的直流（DC）电化学沉积（ECD）通常会产生多孔的、粘附较弱的层。本研究引入了直流偏置交流（AC） ECD，通过将10 V正弦波形叠加到2.5、5.0和7.5 V直流偏置上，来调节Ti-6Al-4V上HA的生长。增加直流偏压改变了沉积模式，导致从短晶到细长的、相互连接的针状网络的形态演变。x射线衍射显示HA反射增强，表明结晶度增强，表面粗糙度和亲水性也增加。动电位极化具有较好的耐蚀性，在2.5 VDC下，其腐蚀系数最低，为（3.17±0.05）× 10−8 A cm−2，保护效率为（91±4）%。所有涂层都促进了模拟体液中磷灰石的次生形成。这种方法为设计致密、耐腐蚀的HA层提供了可调的低温途径。

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引用次数: 0

Effects of Cr3C2–VC on the microstructure and mechanical properties of low–Co WC hard alloy by vacuum pressureless sintering Cr3C2-VC对真空无压烧结低co WC硬质合金组织和力学性能的影响

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-13 DOI: 10.1016/j.vacuum.2026.115086

Sizhuo Bao , Yi Cui , Qianglong He , Aiyang Wang , Weimin Wang

A high-performance WC–0.5 wt% Co hard alloy with uniform and fine grains are successfully prepared in a vacuum pressureless sintering furnace. The effects of Cr₃C₂–VC content on the microstructural evolution and mechanical properties of WC hard materials are examined. The results show that the VC–Cr₃C₂ considerably inhibits the abnormal growth of WC grains, and they exhibit pronounced refinement. Moreover, VC–Cr₃C₂ influences the WC grain morphology. With the addition of VC–Cr₃C₂, sharp triangular WC grains with multisteps and partly rounded WC grains form, resulting in incomplete WC intergranular contact and reduced interfacial energy. The sample with 0.35 wt% Cr₃C₂–0.15 wt% VC has optimal comprehensive mechanical properties. Its average grain size, relative density, Vickers hardness, transverse rupture strength, and fracture toughness are 363 nm, 99.28 %, 28.7 GPa, 1350 MPa, and 7.36 MPa‧m^1/2, respectively. The strengthening and toughening mechanisms of low–Co content WC hard materials are attributed to the formation of dense, homogeneous WC nanograins. This study provides a new strategy for fabricating high-performance low–Co content WC cemented carbide.

在真空无压烧结炉中成功制备了WC-0.5 wt% Co晶粒均匀细小的高性能硬质合金。研究了Cr3C2-VC含量对WC硬质材料显微组织演变和力学性能的影响。结果表明：VC-Cr3C2明显抑制WC晶粒的异常生长，WC晶粒细化明显；VC-Cr3C2对WC晶粒形貌有影响。VC-Cr3C2的加入使WC晶间接触不完全，界面能降低。含0.35 wt% Cr3C2-0.15 wt% VC的样品综合力学性能最佳。平均晶粒尺寸、相对密度、维氏硬度、横向断裂强度和断裂韧性分别为363 nm、99.28%、28.7 GPa、1350 MPa和7.36 MPa·m1/2。低co含量WC硬质材料的强化和增韧机制归因于致密、均匀的WC纳米颗粒的形成。本研究为制备高性能低co含量WC硬质合金提供了新思路。

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引用次数: 0

Thickness and stoichiometry dependence of the electronic structure of NiO/Ag(001) ultrathin films NiO/Ag（001）超薄膜电子结构与厚度及化学计量的关系

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-12 DOI: 10.1016/j.vacuum.2026.115078

Jayanta Das

Epitaxial NiO films of varying thickness were grown on Ag(001) substrate by molecular beam epitaxy under optimized growth condition and characterized in situ using low-energy electron diffraction (LEED) and photoemission spectroscopy. LEED patterns confirm high crystalline order and reveal coexisting (1 × 2) and (2 × 1) antiferromagnetically reconstructed surface domains in ultrathin films. Angle-resolved ultraviolet photoemission (ARPES) measurements show weakly dispersive Ni

3 d

-O

2 p

hybridized bands along

\bar{Γ}

-

\bar{X}

and

\bar{Γ}

-

\bar{M}

directions. Core-level characteristic Ni 2p multiplet features, whose intensity and satellite structure evolve with film thickness and oxygen stoichiometry, were probed by x-ray photoemission. Enhanced nonlocal screening is evident in the ultrathin limit. Comparison of ARPES data with reported theoretical calculations and experimental results facilitates a deeper interpretation of the observed features and validate the reliability and consistency of current findings. Annealing in ultrahigh vacuum creates oxygen vacancies that introduce a non-dispersive defect state near 0.7 eV binding energy (BE). The results establish a comprehensive picture of growth, structure, and electronic evolution in NiO/Ag(001) ultrathin films.

在优化的生长条件下，采用分子束外延技术在Ag（001）衬底上生长出不同厚度的NiO外延薄膜，并利用低能电子衍射（LEED）和光电光谱对其进行了原位表征。LEED模式证实了超薄膜的高晶体有序性，并揭示了超薄膜中共存的（1 × 2）和（2 × 1）反铁磁重构表面域。角度分辨紫外发射（ARPES）测量显示沿Γ¯-X¯和Γ¯-M¯方向的弱色散Ni 3d-O - 2p杂化带。利用x射线光发射技术研究了Ni - 2p多组核能级特征，其强度和卫星结构随薄膜厚度和氧化学计量的变化而变化。在超薄范围内，非局部筛选明显增强。将ARPES数据与已报道的理论计算和实验结果进行比较，有助于更深入地解释观测到的特征，并验证当前发现的可靠性和一致性。在超高真空中退火产生氧空位，在0.7 eV结合能（BE）附近引入非色散缺陷态。研究结果建立了NiO/Ag（001）超薄膜生长、结构和电子演化的全面图景。

{"title":"Thickness and stoichiometry dependence of the electronic structure of NiO/Ag(001) ultrathin films","authors":"Jayanta Das","doi":"10.1016/j.vacuum.2026.115078","DOIUrl":"10.1016/j.vacuum.2026.115078","url":null,"abstract":"<div><div>Epitaxial NiO films of varying thickness were grown on Ag(001) substrate by molecular beam epitaxy under optimized growth condition and characterized <em>in situ</em> using low-energy electron diffraction (LEED) and photoemission spectroscopy. LEED patterns confirm high crystalline order and reveal coexisting (1 × 2) and (2 × 1) antiferromagnetically reconstructed surface domains in ultrathin films. Angle-resolved ultraviolet photoemission (ARPES) measurements show weakly dispersive Ni <span><math><mrow><mn>3</mn><mi>d</mi></mrow></math></span>-O <span><math><mrow><mn>2</mn><mi>p</mi></mrow></math></span> hybridized bands along <span><math><mover><mrow><mi>Γ</mi></mrow><mo>¯</mo></mover></math></span>-<span><math><mover><mrow><mi>X</mi></mrow><mo>¯</mo></mover></math></span> and <span><math><mover><mrow><mi>Γ</mi></mrow><mo>¯</mo></mover></math></span>-<span><math><mover><mrow><mi>M</mi></mrow><mo>¯</mo></mover></math></span> directions. Core-level characteristic Ni 2p multiplet features, whose intensity and satellite structure evolve with film thickness and oxygen stoichiometry, were probed by x-ray photoemission. Enhanced nonlocal screening is evident in the ultrathin limit. Comparison of ARPES data with reported theoretical calculations and experimental results facilitates a deeper interpretation of the observed features and validate the reliability and consistency of current findings. Annealing in ultrahigh vacuum creates oxygen vacancies that introduce a non-dispersive defect state near 0.7 eV binding energy (BE). The results establish a comprehensive picture of growth, structure, and electronic evolution in NiO/Ag(001) ultrathin films.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"246 ","pages":"Article 115078"},"PeriodicalIF":3.9,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977733","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

Degradation behavior of vertical gallium nitride light-emitting diodes in salt spray environments: A study based on electrical and material analysis techniques, integrated with a smart protection circuit application perspective 垂直氮化镓发光二极管在盐雾环境中的降解行为：基于电气和材料分析技术的研究，结合智能保护电路的应用前景

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-12 DOI: 10.1016/j.vacuum.2026.115090

Shao-Ruei Yang , Chun-Yen Yang , En-Ting He , Chia-Feng Lin , Jing- Jenn Lin , Hsiang Chen , Yung-Hui Li

This study systematically investigates the degradation behavior of vertical Gallium Nitride (GaN) Light-Emitting Diodes (LEDs) under salt spray corrosion in high-humidity and high-salinity environments.

Combining electrical measurements with advanced material analysis techniques—specifically Optical Microscopy (OM), Scanning Electron Microscopy(SEM), Energy-Dispersive X-ray Spectroscopy(EDS), Transmission Electron Microscopy(TEM), and X-ray Diffraction(XRD), the research found that corrosive ions penetrate the GaN layer, causing electrochemical etching and defect formation. This damage critically compromises the P-type electrode interface.

This structural breakdown leads to hindered carrier injection and interrupted conductive paths, resulting in degraded device performance characterized by increased leakage current, reduced forward current, exacerbated current crowding, and decreased emission uniformity.

The findings highlight the critical role of the P-type bottom electrode's structural stability for vertical GaN LED reliability, providing crucial data support for future packaging design, material selection, and the development of smart protection circuits to enhance the long-term stability of LEDs in harsh conditions.

本研究系统地研究了高湿、高盐环境下垂直氮化镓发光二极管（GaN light emitting diode, led）在盐雾腐蚀下的降解行为。结合电气测量和先进的材料分析技术-特别是光学显微镜（OM），扫描电子显微镜（SEM），能量色散x射线光谱（EDS），透射电子显微镜（TEM）和x射线衍射（XRD），研究发现腐蚀离子穿透GaN层，导致电化学蚀刻和缺陷形成。这种损伤严重损害了p型电极界面。这种结构击穿导致载流子注入受阻和导电路径中断，导致器件性能下降，其特征是泄漏电流增加，正向电流减少，电流拥挤加剧，发射均匀性下降。研究结果强调了p型底部电极的结构稳定性对垂直GaN LED可靠性的关键作用，为未来的封装设计、材料选择和智能保护电路的开发提供了关键数据支持，以增强LED在恶劣条件下的长期稳定性。

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引用次数: 0

Superconducting fluctuations and quasiparticle recombination times in disordered Mo2N thin films 无序Mo2N薄膜中的超导涨落和准粒子复合次数

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-11 DOI: 10.1016/j.vacuum.2026.115087

N. Haberkorn , Jeehoon Kim

Disordered Mo₂N thin films exhibit a superconducting transition up to 7.7 K, together with a weak metal–insulator crossover and positive magnetoresistance emerging already near 30 K, well above the critical temperature (T_c). This ≈ 30 K signature persists in both thick and ultrathin films, and even becomes more pronounced in the ultrathin limit, indicating an atomic-scale origin largely insensitive to thickness. The magnetoresistance is nearly isotropic with respect to field orientation and persists up to 16 T, pointing to unexpectedly robust superconducting fluctuations extending far above T_c. For a film with T_c = 7.7 K, by fitting the field-dependent conductance within the weak-localization plus Maki–Thompson framework for T > 8 K, we extract the inelastic scattering time (τ_i), which is ≈ 5 ps near T_c and decreases systematically with temperature. A decomposition of the inelastic rate reveals electron–electron and electron–phonon channels corresponding to characteristic times of ≈ 10 ps and ≈ 50 ps, respectively. These values agree with previous estimates from vortex critical-velocity measurements and underscore molybdenum nitride as a promising platform for fast radiation detectors.

无序Mo2N薄膜表现出高达7.7 K的超导转变，以及弱金属-绝缘体交叉和已经在30 K附近出现的正磁阻，远高于临界温度（Tc）。这种≈30k的特征在厚膜和超薄膜中都存在，甚至在超薄极限下变得更加明显，表明原子尺度上的起源对厚度不敏感。磁电阻在磁场方向上几乎是各向同性的，并持续到16t，这表明超导波动出乎意料地强劲，远远超过Tc。对于Tc = 7.7 K的薄膜，通过拟合T >； 8 K的弱局域化和Maki-Thompson框架内的场相关电导，我们提取了非弹性散射时间τi，它在Tc附近≈5 ps，并随着温度的升高而逐渐减小。非弹性速率的分解揭示了电子-电子和电子-声子通道分别对应于≈10 ps和≈50 ps的特征时间。这些值与先前涡临界速度测量的估计一致，并强调了氮化钼作为快速辐射探测器的有前途的平台。

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引用次数: 0

Effect of joining parameters on mechanical properties of TLP bonded K416B/GH4648 joint reinforced by BCC and γ′ phases 连接参数对BCC和γ′相增强TLP粘结K416B/GH4648接头力学性能的影响

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-10 DOI: 10.1016/j.vacuum.2026.115075

Mingze Ran , Faming Shen , Xin Zheng , Zenghui Cai , Yi Zheng , Boyu Zhang , Wei Ke , Jia Xie , Deshui Yu , Bo Zhang , Qing Chang , Zhan Sun , Lixia Zhang

In order to address the issues of low seam strength in nickel-based TLP joints, a new Fe-Co-Ni-Al-B multi-component alloy filler was designed. The microstructure of the filler and the microstructure and mechanical properties of TLP joints of GH4648 and K416B using Fe₇(CoNi)₆₃Al₁₄B₁₆ filler were investigated. Furthermore the effects of joining parameters on the microstructure and mechanical properties of the joint were discussed. The results show that the Fe₇(CoNi)₆₃Al₁₄B₁₆ multi-component alloy filler exhibits a dual-phase microstructure consisting of FCC and BCC phases. Precipitated phases within the seam primarily consisted of the matrix FCC phase, BCC phase, M₂₃B₆, Cr-Mo-W boride, and γ′-(Ni, Co)₃Al precipitates on the matrix FCC phase. At a holding temperature of 1160 °C for 120 min, the maximum shear strength of the joint at room temperature and 900 °C is 705 MPa and 380 MPa, respectively. The joints exhibit mixed-mode fracture behavior, characterized by both transcrystalline and intergranular features. The maximum differences in hardness and elastic modulus between the bonding seam and the DAZ are 28.77 GPa and 0.37 GPa, respectively. The microhardness and elastic modulus values of the joint were evenly distributed. This work provides a new idea for the TLP bonding of dissimilar superalloys utilized in the manufacturing of aero-engine turbine guide.

为解决镍基TLP接头接缝强度低的问题，设计了一种新型Fe-Co-Ni-Al-B多组分合金填料。研究了Fe7(CoNi)63Al14B16钎料对GH4648和K416B TLP接头组织和力学性能的影响。讨论了连接参数对接头组织和力学性能的影响。结果表明：Fe7(CoNi)63Al14B16多组分合金填料呈现FCC相和BCC相的双相组织；焊缝内析出相主要为基体FCC相、BCC相、M23B6相、Cr-Mo-W硼化物相和基体FCC相上的γ′-(Ni, Co)3Al相。保温温度为1160℃，保温120 min时，接头在室温和900℃时的最大抗剪强度分别为705 MPa和380 MPa。接头表现出跨晶和沿晶混合断裂行为。结合缝与DAZ的硬度和弹性模量最大差异分别为28.77 GPa和0.37 GPa。接头的显微硬度和弹性模量分布均匀。本工作为航空发动机涡轮导向器中异种高温合金的TLP粘接提供了新的思路。

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引用次数: 0

The effect of an innovative rejuvenation heat treatment on the microstructure and creep performance of DS-GTD 111 superalloy 创新回火热处理对DS-GTD 111高温合金组织和蠕变性能的影响

IF 3.9 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2026-01-10 DOI: 10.1016/j.vacuum.2025.115056

Lijie Qiao , Yunpeng Fan , Xinbao Zhao , Mingyang Yu , Yu Zhou , Yuan Cheng , Quanzhao Yue , Wanshun Xia , Yuefeng Gu , Ze Zhang

This study proposes a novel rejuvenation heat treatment (RHT) strategy designed to preserve grain-boundary M₂₃C₆ carbides, aiming to regenerate the creep performance of long-term serviced directionally solidified turbine blades. Microstructural characterization reveals section-dependent degradation mechanisms: while the root section mainly exhibits dislocation networks, the airfoil suffers from severe secondary γ′ coarsening, stacking fault shearing, and MC carbide decomposition into brittle η phase. The applied RHT successfully eliminates the deleterious η phase, dissolves coarsened γ′, and refines the strengthening precipitates from 1 μm to 0.35 μm, thereby restoring the alloy's ability to form regular interfacial rafts under stress. Consequently, post-recovery heat treatment yields about 100 % increase in creep life at both blade airfoil and root sections. However, it is found that irreversible Cr-enrichment at airfoil grain boundaries induces spheroidal M₂₃C₆ carbides, which accelerates failure. These findings elucidate the microstructural limits of rejuvenation and offer a pathway for optimizing life-extension strategies for critical turbine components.

本研究提出了一种新的再生热处理（RHT）策略，旨在保留晶界M23C6碳化物，旨在恢复长期服役的定向凝固涡轮叶片的蠕变性能。显微组织表征揭示了与截面相关的退化机制：当翼型的根截面主要表现为位错网络时，翼型遭受严重的二次γ′粗化、层错剪切和MC碳化物分解为脆性η相。RHT成功地消除了有害的η相，溶解了粗化的γ′，并将强化相从1 μm细化到0.35 μm，从而恢复了合金在应力作用下形成规则界面raft的能力。因此，后恢复热处理产生的蠕变寿命增加约100%在叶片翼型和根部部分。然而，在翼型晶界处不可逆的cr富集导致了球状的M23C6碳化物，加速了失效。这些发现阐明了再生的微观结构限制，并为优化关键涡轮部件的延长寿命策略提供了途径。

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引用次数: 0