Acta Materialia最新文献_第10页

Sequential Bayesian Inference of the GTN damage model using multimodal experimental data 基于多模态实验数据的GTN损伤模型序贯贝叶斯推断

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-08 DOI: 10.1016/j.actamat.2026.121902

Mohammad Ali Seyed Mahmoud , Dominic Renner , Ali Khosravani , Surya R. Kalidindi

Reliable parameter identification in ductile damage models remains challenging because the salient physics of damage progression are localized to small regions in material responses, and their signatures are often diluted in specimen-level measurements. Here, we propose a sequential Bayesian Inference (BI) framework for the calibration of the Gurson–Tvergaard–Needleman (GTN) model using multimodal experimental data (i.e., the specimen-level force–displacement (F–D) measurements and the spatially resolved digital image correlation (DIC) strain fields). This calibration approach builds on a previously developed two-step BI framework that first establishes a low-computational-cost emulator for a physics-based simulator (here, a finite element model incorporating the GTN material model) and then uses the experimental data to sample posteriors for the material model parameters using the Transitional Markov Chain Monte Carlo (T-MCMC). A central challenge to the successful application of this BI framework to the present problem arises from the high-dimensional representations needed to capture the salient features embedded in the F–D curves and the DIC fields. In this paper, it is demonstrated that Principal Component Analysis (PCA) provides low-dimensional representations that make it possible to apply the BI framework to the problem. Most importantly, it is shown that the sequence in which the BI is applied has a dramatic influence on the results obtained. Specifically, it is observed that applying BI first on F–D curves and subsequently on the DIC fields produces improved estimates of the GTN parameters. Possible causes for these observations are discussed in this paper, using AA6111 aluminum alloy as a case study.

在延性损伤模型中，可靠的参数识别仍然具有挑战性，因为损伤进展的显著物理特性局限于材料响应的小区域，并且它们的特征在样品级测量中经常被稀释。在这里，我们提出了一个顺序贝叶斯推理（BI）框架，用于使用多模态实验数据（即样品级力-位移（F-D）测量和空间分辨数字图像相关（DIC）应变场）校准Gurson-Tvergaard-Needleman （GTN）模型。这种校准方法建立在先前开发的两步BI框架的基础上，该框架首先为基于物理的模拟器（这里是一个包含GTN材料模型的有限元模型）建立一个低计算成本的模拟器，然后使用实验数据使用过渡马尔可夫链蒙特卡罗（T-MCMC）对材料模型参数的后验进行采样。将这个BI框架成功应用于当前问题的一个核心挑战来自捕获嵌入在F-D曲线和DIC域中的显著特征所需的高维表示。在本文中，证明了主成分分析（PCA）提供了低维表示，使得将BI框架应用于问题成为可能。最重要的是，结果表明，应用BI的顺序对得到的结果有很大的影响。具体来说，可以观察到首先在F-D曲线上应用BI，然后在DIC场上应用BI，可以提高对GTN参数的估计。本文以AA6111铝合金为例，讨论了产生这些现象的可能原因。

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引用次数: 0

Corrigendum to 'Behavior of Fe-based alloys in a liquid lead-bismuth environment under simultaneous proton irradiation and corrosion' 《铁基合金在质子辐照和腐蚀下在液态铅铋环境中的行为》的勘误

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-08 DOI: 10.1016/j.actamat.2026.121895

Ertugrul Demir , Saikumaran Ayyapan , Weiyue Zhou , Wande Cairang , Kevin B. Woller , Michael P. Short , Djamel Kaoumi

引用次数: 0

Quantitative study of precipitation strengthening effects of T1 phase in Al–Cu–Li–Mg–Ag alloy: Role of nonuniform spatial distribution Al-Cu-Li-Mg-Ag合金中T1相析出强化效应的定量研究：非均匀空间分布的作用

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-07 DOI: 10.1016/j.actamat.2026.121907

Xin Wang , Xusheng Yang , Weijiu Huang , Yunchang Xin , Dehong Lu , Xianghui Zhu , Mengdi Li , Yanzheng Guo

The plate–shaped T₁ phase serves as the primary strengthening precipitate in the advanced Al–Li alloys, and its spatial distribution is a critical factor affecting alloy performance. In this study, electron backscatter diffraction (EBSD), focused ion beam (FIB), and transmission electron microscopy (TEM) were combined to investigate the spatial distribution of T₁ plates in specific crystal orientations. The results revealed that the preferred T₁ variants mostly precipitated on the habit plane with the maximum Schmid factor. A modified strengthening model was developed considering the uneven distribution of T₁ phase. To verify the accuracy of this model, yield strength tests were performed on a single grain using nanoindentation. The analysis indicated that precipitation strengthening could be substantially overestimated in grains containing preferential T₁ variants. This study provides a quantitative and precise evaluation of precipitation strengthening in Al–Cu–Li–Mg–Ag alloys, considering specific crystal orientation and spatial distribution.

板状T1相是高级Al-Li合金的主要强化相，其空间分布是影响合金性能的关键因素。本研究采用电子背散射衍射（EBSD）、聚焦离子束（FIB）和透射电镜（TEM）相结合的方法研究了T1板在特定晶体取向上的空间分布。结果表明，首选T1型主要在习惯面析出，施密德因子最大。考虑T1相的不均匀分布，建立了改进的强化模型。为了验证该模型的准确性，使用纳米压痕对单个晶粒进行了屈服强度测试。分析表明，在含有优先T1变异体的晶粒中，降水强化可能被大大高估。考虑到特定的晶体取向和空间分布，本研究为Al-Cu-Li-Mg-Ag合金的沉淀强化提供了定量和精确的评价。

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引用次数: 0

High temperature zirconium alloys Zr-Al-Sn-(Si,Cr,V) by near-α titanium analogy 高温锆合金Zr-Al-Sn-（Si,Cr，V）的近似[公式省略]钛类比

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-07 DOI: 10.1016/j.actamat.2025.121891

J.P. Magnussen , Í. Carneiro , K. Ma , C. Coleman , A. Wisbey , H. Swan , A.J. Knowles

The use of conventional zirconium alloys at temperatures above 400 °C is limited by high temperature strength and creep resistance. This has prevented the consideration of zirconium alloys for fusion and Generation IV fission plant designs operating at 500 °C–1000 °C. The physical metallurgy of zirconium is similar to titanium which has seen alloying advances allowing application temperatures up to 600 °C. Although the oxidation resistance of zirconium-based alloys is expected to be poor, in a water environment, new Generation-IV and fusion reactors are designed to operate using alternative coolants such as liquid metals and molten salts. Therefore, a new class of zirconium alloys in the Zr-Al-Sn-(Si,Cr,V) system, designed by analogy to near-

α

titanium alloys, were synthesised by arc melting and processed in a sequence of homogenisation, hot/cold rolling, recrystallisation, and ageing treatments. Microscopy and diffraction identified a refined fully lath grain structure reinforced by nanoscale lamellar or discrete coherent Zr₃Al precipitates, with morphology and crystal structure differing with ageing times. Additionally alloying with Si, Cr, and V respectively leads to Zr₂Si, ZrCr₂, and ZrV₂ incoherent precipitates. Tensile testing revealed a strengthening effect by Al, but with significant changes to ductility on ageing depending on the evolution of Zr₃Al. Creep testing showed creep rates orders of magnitude better than conventional Zircaloy-4 and nuclear ferritic/martensitic steels, approaching near-

α

Ti alloys. The present work offers new insights and perspectives into how high-temperature zirconium alloys might be designed to meet the requirements for fusion and Gen-IV fission.

传统锆合金在400°C以上的温度下的使用受到高温强度和抗蠕变性能的限制。这阻碍了在500°C - 1000°C运行的聚变和第四代裂变工厂设计中考虑锆合金。锆的物理冶金与钛相似，钛的合金化进展使其应用温度高达600°C。虽然锆基合金的抗氧化性预计会很差，但在水环境中，新的第四代和聚变反应堆被设计为使用液态金属和熔盐等替代冷却剂运行。因此，采用电弧熔合法制备了一类新型Zr-Al-Sn-（Si,Cr，V）系锆合金，并对其进行了均匀化、冷轧、再结晶和时效处理。显微和衍射鉴定出由纳米级片层状或离散相干Zr3Al析出相增强的精细的全板条晶粒结构，其形貌和晶体结构随时效时间的不同而不同。另外，分别与Si、Cr和V合金会产生Zr2Si、ZrCr2和ZrV2非共相。拉伸试验表明，Al对Zr3Al合金具有强化作用，但随着Zr3Al的演化，合金的时效延展性发生了显著变化。蠕变试验表明，其蠕变速率比传统的锆合金-4和核铁素体/马氏体钢好几个数量级，接近-α Ti合金。目前的工作为如何设计高温锆合金以满足聚变和Gen-IV裂变的要求提供了新的见解和视角。

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引用次数: 0

Direct observation of nanoscale pinning centers in Ce(Co0.8Cu0.2)5.4 permanent magnets Ce(Co0.8Cu0.2)5.4永磁体中纳米级钉钉中心的直接观察

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-06 DOI: 10.1016/j.actamat.2026.121906

Nikita Polin , Shangbin Shen , Fernando Maccari , Alex Aubert , Esmaeil Adabifiroozjaei , Tatiana Smoliarova , Yangyiwei Yang , Xinren Chen , Yurii Skourski , Alaukik Saxena , András Kovács , Rafal E. Dunin-Borkowski , Michael Farle , Bai-Xiang Xu , Leopoldo Molina-Luna , Oliver Gutfleisch , Baptiste Gault , Konstantin Skokov

Permanent magnets containing rare earth elements are essential components for the electrification of society. Ce(Co_1-xCu_x)₅ permanent magnets are a model system known for their substantial coercivity, yet the underlying mechanism remains unclear. Here, we investigate Ce(Co_0.8Cu_0.2)_5.4 magnets with a coercivity of ∼1 T. Using transmission electron microscopy (TEM) and atom probe tomography (APT), we identify a nanoscale cellular structure formed by spinodal decomposition. Cu-poor cylindrical cells (∼5–10 nm in diameter, ∼20 nm long) have a disordered CeCo₅-type structure and a composition Ce(Co_0.9Cu_0.1)_5.3. Cu-rich cell boundaries are ∼ 5 nm thick and exhibit a modified CeCo₅ structure, with Cu ordered on the Co sites and a composition Ce(Co_0.7Cu_0.3)_5.0. Micromagnetic simulations demonstrate that the intrinsic Cu concentration gradients up to 12 at.% Cu/nm lead to a spatial variation in magnetocrystalline anisotropy and domain wall energy, resulting in effective pinning and high coercivity. Compared to Sm₂Co₁₇-type magnets, Ce(Co_0.8Cu_0.2)_5.4 displays a finer-scale variation of conventional pinning with lower structural and chemical contrast in its underlying nanostructure. The identification of nanoscale chemical segregation in nearly single-phase Ce(Co_0.8Cu_0.2)_5.4 magnets provides a microstructural basis for the long-standing phenomenon of "giant intrinsic magnetic hardness" in systems such as SmCo_5-xM_x, highlighting avenues for designing rare-earth-lean permanent magnets via controlled nanoscale segregation.

含有稀土元素的永磁体是社会电气化的重要组成部分。Ce(Co1-xCux)5永磁体是一种以其强大的矫顽力而闻名的模型系统，但其潜在的机制尚不清楚。在这里，我们研究了矫顽力为1 t的Ce(Co0.8Cu0.2)5.4磁体，利用透射电子显微镜（TEM）和原子探针断层扫描（APT），我们发现了一个由spinodal分解形成的纳米级细胞结构。贫铜圆柱电池（直径约5-10 nm，长约20 nm）具有无序的ceco5型结构，组成为Ce(Co0.9Cu0.1)5.3。富Cu细胞边界厚约5 nm，呈现出修饰的CeCo5结构，Cu在Co位点上有序排列，组成为Ce(Co0.7Cu0.3)5.0。微磁模拟结果表明，本构铜浓度梯度可达12 at。% Cu/nm导致磁晶各向异性和畴壁能的空间变化，从而产生有效的钉住和高矫顽力。与sm2co17型磁体相比，Ce(Co0.8Cu0.2)5.4表现出传统钉钉的细微变化，其底层纳米结构的结构和化学对比较低。近单相Ce(Co0.8Cu0.2)5.4磁体中纳米级化学偏析的发现为SmCo5-xMx等体系中长期存在的“巨本征磁硬度”现象提供了微观结构基础，为通过可控纳米偏析设计稀土贫永磁体指明了途径。

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引用次数: 0

Composition-driven nanotwin engineering in sputtered Ni-Fe and Ni-Cr films: linking fault energetics to twin thickness 溅射Ni-Fe和Ni-Cr薄膜中成分驱动的纳米孪晶工程：将故障能量与孪晶厚度联系起来

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-06 DOI: 10.1016/j.actamat.2025.121890

Mohammad Hadi Yazdani , Aoyan Liang , Ashley J. Maldonado Otero , Yi Liu , Diana Farkas , Andrea M. Hodge , Timothy J. Rupert , Irene J. Beyerlein , Paulo S. Branicio

In this study, molecular dynamics (MD) simulations are combined with magnetron co-sputtering experiments to examine how Ni-Fe and Ni-Cr compositions affect defect energetics and twin microstructure in thin films. These simulations represent the first direct modeling of nanotwin formation during atomistic thin film deposition. Ensemble MD simulations reveal substantial stochastic variability in grain structure and twin development across deposition runs, yet clear compositional trends emerge. Cr-rich Ni-Cr alloys form dense twin networks with narrow spacing, while Fe-rich Ni-Fe alloys exhibit fewer twins with significantly larger spacing. Scanning transmission electron microscopy (STEM) of Ni-Cr films confirms the predicted high twin density and reduced spacing, validating the link between alloy composition and growth twin formation. Notably, both simulations and experiments reveal that the distribution of twin boundary spacings is log-normal, reflecting the stochastic nature of twin nucleation during deposition. Composition-dependent maps from MD simulations further demonstrate that small variations in Ni-Cr and Ni-Fe chemistry can systematically tune twin boundary formation and enable the design of nanoscale twin architectures. This integrated computational-experimental study establishes a clear inverse relationship between stacking fault energy and average twin spacing, offering a pathway for engineering nanostructured coatings with tailored twin networks and enhanced properties.

在这项研究中，分子动力学（MD）模拟与磁控共溅射实验相结合，研究了Ni-Fe和Ni-Cr成分对薄膜缺陷能量学和孪晶结构的影响。这些模拟代表了原子薄膜沉积过程中纳米孪晶形成的第一个直接模型。集合MD模拟揭示了沉积过程中晶粒结构和孪晶发育的大量随机变化，但清晰的成分趋势出现了。富cr的Ni-Cr合金形成致密的孪晶网络，孪晶网络间距小，而富fe的Ni-Fe合金孪晶网络较少，孪晶网络间距大。Ni-Cr薄膜的扫描透射电子显微镜（STEM）证实了预测的高孪晶密度和减小孪晶间距，验证了合金成分与生长孪晶形成之间的联系。值得注意的是，模拟和实验都表明，孪晶边界间距的分布是对数正态分布，反映了沉积过程中孪晶成核的随机性。MD模拟的成分依赖图进一步表明，Ni-Cr和Ni-Fe化学的微小变化可以系统地调整孪晶边界的形成，并使纳米孪晶结构的设计成为可能。这项综合计算-实验研究建立了层错能与平均孪晶间距之间的明确反比关系，为具有定制孪晶网络和增强性能的工程纳米结构涂层提供了途径。

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引用次数: 0

Quantifying changes to solute segregation behaviour at interfaces in additively manufactured Ti-6Al-4V 增材制造Ti-6Al-4V界面溶质偏析行为的定量变化

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-06 DOI: 10.1016/j.actamat.2026.121904

Andrew J. Breen , William J. Davids , Hansheng Chen , Han Lin Mai , Keita Nomoto , Xiangyuan Cui , Xiaozhou Liao , Sophie Primig , Simon P. Ringer

Electron powder bed fusion has emerged as a promising additive manufacturing process for producing Ti-6Al-4V components with complex geometries. Although prior work has examined microstructural evolution phenomena including how thermal history influences the prevalence of specific α/α grain boundary misorientation intervariants governed by the Burgers orientation relationship between the α and β phases, the solute segregation behaviour at these interfaces remains poorly understood. This study employs correlative transmission Kikuchi diffraction and atom probe tomography to quantify the Gibbsian interfacial excess of V, Fe, and Al across multiple interfaces in electron powder bed fusion produced Ti-6Al-4V. V and Fe exhibited enrichment, while Al was depleted, with V segregation generally increasing with boundary misorientation. Spatial variations in segregation were observed across interface planes, although no consistent trend with boundary curvature was identified. First-principles calculations were also performed on model α/α grain boundaries to evaluate segregation energetics, confirming a thermodynamic preference for V enrichment and Al depletion. The agreement between experimental observations and theoretical predictions highlights the influence of local defect structures and atomic-scale interactions on segregation behaviour. These findings improve understanding of grain boundary chemistry in additively manufactured Ti alloys and provide a basis for future grain boundary engineering approaches aimed at tailoring interfacial properties.

电子粉末床熔合已成为一种有前途的增材制造工艺，用于生产具有复杂几何形状的Ti-6Al-4V组件。虽然之前的工作已经研究了微观结构演化现象，包括热历史如何影响由α和β相之间的Burgers取向关系控制的特定α/α晶界错取向互变的流行，但这些界面上的溶质偏析行为仍然知之甚少。本研究采用相关透射Kikuchi衍射和原子探针层析成像技术，量化了电子粉末床熔合制备Ti-6Al-4V过程中V、Fe和Al在多个界面上的Gibbsian界面过剩。V和Fe呈现富集，而Al呈现贫态，随着边界取向的错向，V的偏析普遍加剧。在不同的界面面上观察到偏析的空间变化，但没有发现与边界曲率一致的趋势。在模型α/α晶界上进行第一性原理计算来评估偏析能量学，证实了V富集和Al耗尽的热力学偏好。实验观察和理论预测之间的一致性突出了局部缺陷结构和原子尺度相互作用对偏析行为的影响。这些发现提高了对增材制造钛合金晶界化学的理解，并为未来旨在定制界面性能的晶界工程方法提供了基础。

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引用次数: 0

Mechano-electrochemical fabrication of self-supported Ag electrode with Ni surface single atom for hydrogen production Ni表面单原子自支撑银电极的机械电化学制备

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-05 DOI: 10.1016/j.actamat.2026.121905

Jing-Qian Zhang , Zi-Ang Ma , Cong Xi , Yan Zhang , Wen-Xuan Lv , Chuan-Qi Cheng , Chun-Yan Han , Jing-Jing Wang , Shuang Li , Rui Zhang , Qianjin Guo , Jing Yang , Cun-Ku Dong , Hui Liu , Peng-Fei Yin , Xi-Wen Du

Metastable structures usually possess unique atomic and electronic configurations and thus show high potential on catalyzing chemical reactions. Among various metastable structures, surface single-atom alloys (SSAAs) attract widespread attention due to their ability to expose all dissimilar atoms on the surface, thereby regulating the electronic structure significantly. However, the synthesis of SSAAs remains a challenge due to the lack of effective methodology. Herein, we report a universal mechano-electrochemical technique for the synthesis of various SSAAs. Taking the Ni-Ag system as an example, the mechano-electrochemical process first drives nickel ions into Ag lattice, and then the embedded nickel ions are electrolytic reduced into nickel atoms, which are preferentially stabilized at the outermost surface, leading to the formation of SSAA. The produced self-supported electrode with SSAA exhibits excellent catalytic performance towards hydrogen evolution reaction, surpassing Ni-based catalysts and even Pt/C. This mechano-electrochemical technique can be applied to various immiscible alloy systems for the fabrication of SSAAs and then transform catalytically inert metals into high-performance catalysts.

亚稳态结构通常具有独特的原子和电子构型，因此在催化化学反应方面表现出很大的潜力。在各种亚稳结构中，表面单原子合金（SSAAs）由于能够将表面所有异种原子暴露，从而显著调节电子结构而受到广泛关注。然而，由于缺乏有效的方法，SSAAs的合成仍然是一个挑战。在此，我们报道了一种通用的机械电化学技术来合成各种SSAAs。以Ni-Ag体系为例，机械电化学过程首先驱动镍离子进入Ag晶格，然后嵌入的镍离子被电解还原成镍原子，镍原子优先稳定在最外层表面，从而形成SSAA。制备的SSAA自支撑电极对析氢反应的催化性能优于ni基催化剂，甚至优于Pt/C催化剂。这种机械-电化学技术可以应用于各种非混相合金体系，用于制备SSAAs，然后将催化惰性金属转化为高性能催化剂。

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引用次数: 0

Unraveling the composition-dependent CMAS corrosion resistance in A6B2O17 (A = Hf, Zr; B = Ta, Nb) ceramics: An experimental and first-principles study A6B2O17 （A = Hf, Zr; B = Ta, Nb）陶瓷抗CMAS腐蚀性能的实验与第一性原理研究

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-05 DOI: 10.1016/j.actamat.2026.121903

Sai Liu , Xiaopeng Hu , Guangsheng Chen , Shenxiang Luo , Yu Zou , Jinwei Guo , Wang Zhu

Despite their promise as candidates for thermal barrier coatings (TBCs), the engineering application of A₆B₂O₁₇ (A = Hf, Zr; B = Ta, Nb) ceramics is currently limited by a lack of comprehensive understanding regarding their CMAS corrosion behavior and underlying mechanisms. This paper addresses this gap by elucidating the governing effects of compositional modulation and corrosion conditions on the CMAS corrosion performance of these ceramics, integrating experimental and first-principles theoretical approaches. The results demonstrate that while all compositions exhibit similar corrosion products and resistance mechanisms, A₆Ta₂O₁₇ (particularly Hf₆Ta₂O₁₇) displays superior corrosion resistance. This enhanced performance is attributed to a combination of factors, including its exceptional thermodynamic stability, reduced Ca²⁺ diffusivity, the significant barrier effect of its dense corrosion product layer, and stronger interfacial bonding strength. Corrosion-induced spallation in Zr₆B₂O₁₇ primarily stems from two factors: the phase transformation of ZrO₂ and an inherently weak interfacial bonding strength. Moreover, while an elevated Ca/Si ratio increases the aggressiveness of CMAS melts, the formation of a dense corrosion product layer on the ceramic surface effectively mitigates this detrimental effect.

尽管A6B2O17 （A = Hf, Zr; B = Ta, Nb）陶瓷有望成为热障涂层（tbc）的候选材料，但由于缺乏对其CMAS腐蚀行为和潜在机制的全面了解，其工程应用目前受到限制。本文通过结合实验和第一性原理理论方法，阐明了成分调制和腐蚀条件对这些陶瓷的CMAS腐蚀性能的控制作用，从而解决了这一空白。结果表明，虽然所有成分的腐蚀产物和耐蚀机理相似，但A6Ta2O17（特别是Hf6Ta2O17）的耐蚀性更强。这种增强的性能归因于多种因素，包括其优异的热力学稳定性，降低的Ca2+扩散率，其致密腐蚀产物层的显著屏障效应，以及更强的界面结合强度。Zr6B2O17的腐蚀剥落主要是由两个因素引起的：ZrO2的相变和固有的弱界面结合强度。此外，虽然Ca/Si比的增加增加了CMAS熔体的侵蚀性，但在陶瓷表面形成的致密腐蚀产物层有效地减轻了这种有害影响。

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引用次数: 0

Precipitation and phase evolution in a Cu-modified near-α titanium alloy designed for additive manufacturing 增材制造用cu改性近α钛合金的析出与相演化

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-01-05 DOI: 10.1016/j.actamat.2026.121901

David Obersteiner , Ehsan Farabi , Sabine C. Bodner , Helmut Clemens , Andreas Landefeld , Sophie Primig , Andreas Stark , José L. Neves , Thomas Klein , Michael Musi

Developing lightweight high-temperature materials with excellent oxidation and creep resistance is crucial for improving efficiency in next-generation aerospace and energy systems. Near-α Ti alloys offer a promising balance of high specific strength, thermal stability, as well as oxidation resistance for such applications. However, exploiting their full potential, especially with additive manufacturing (AM), requires a deep understanding of their microstructural evolution under complex thermal conditions including phase transformations and precipitation pathways. Among various alloying strategies, Cu and Si additions show potential to promote grain refinement and enhance mechanical properties in Ti alloys processed by AM. However, the associated precipitation pathways, particularly those of Cu-rich intermetallics, remain largely unexplored in multicomponent near-α Ti systems. This study investigates phase transformations and precipitation behavior in a novel Cu- and Si-containing near-α Ti alloy using in situ high-energy X-ray diffraction (HEXRD) and small-angle X-ray scattering (SAXS), supported by transmission electron microscopy (TEM) and atom probe tomography (APT). Two intermetallic phases, Ti₂Cu and S2-type (Ti,Zr)₆Si₃ silicides, are identified during continuous heating, each exhibiting distinct precipitation kinetics and thermal stability. SAXS reveals Ti₂Cu precipitation already at ∼460 °C, indicating its potential formation at typical service temperatures (up to ∼600 °C). Quench rate experiments show that Ti₂Cu precipitation can be suppressed at cooling rates above 50 °C/s, while forming between 620 and 500 °C at lower rates. These findings enable the design of heat treatments tailored for controlled precipitation and provide a foundation for future alloy development, contributing to improved efficiency and reliability of high-temperature components.

开发具有优异抗氧化和抗蠕变性能的轻质高温材料对于提高下一代航空航天和能源系统的效率至关重要。近α Ti合金为此类应用提供了高比强度，热稳定性和抗氧化性的良好平衡。然而，要充分利用它们的潜力，特别是增材制造（AM），需要深入了解它们在复杂热条件下的微观结构演变，包括相变和沉淀途径。在多种合金化策略中，Cu和Si的加入有促进增材制造钛合金晶粒细化和提高力学性能的潜力。然而，在多组分近α Ti体系中，相关的沉淀途径，特别是富cu金属间化合物的沉淀途径，在很大程度上仍未被探索。本研究利用原位高能x射线衍射（HEXRD）和小角度x射线散射（SAXS），在透射电子显微镜（TEM）和原子探针断层扫描（APT）的支持下，研究了一种新型含Cu和si的近α Ti合金的相变和沉淀行为。在连续加热过程中，鉴定出Ti2Cu和s2型（Ti,Zr）6Si3硅化物两种金属间相，它们均表现出不同的析出动力学和热稳定性。SAXS显示Ti2Cu已经在~ 460°C析出，表明其在典型使用温度（高达~ 600°C）下的潜在形成。淬火速率实验表明，当冷却速率高于50℃/s时，Ti2Cu的析出可以被抑制，而在620 ~ 500℃时，Ti2Cu的析出则以较低的冷却速率形成。这些发现有助于为控制沉淀设计量身定制的热处理，并为未来的合金开发奠定基础，有助于提高高温部件的效率和可靠性。

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引用次数: 0