IF 4.6 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

International Journal of Refractory Metals & Hard Materials

Pub Date : 2026-08-01 Epub Date: 2026-02-11 DOI: 10.1016/j.ijrmhm.2026.107732

Xiya He, Xiping Guo, Ying Li, Chenyu Hu

Five multi-elemental NbSi based ultrahigh temperature alloys with nominal compositions of Nb-22Ti-14.8Si-4Cr-2.5Al-xCo (x = 0, 1, 2, 4, and 8 at.%) were prepared via vacuum non-consumable arc-melting. The effects of Co addition on the microstructure, nanoindentation hardness, compressive strength and isothermal oxidation resistance at 1250 °C of the alloys were investigated. The results reveal that the content of both the Nbss/γ(Nb,X)₅Si₃ eutectic and the Nbss phase decreases with increasing Co content in the alloys and Co addition promotes the morphological transformation of Nbss toward a dendritic structure. Meanwhile, the addition of Co promotes the formation of new polymorphs of silicide phases; the increase in Co content changes the phase fractions of the alloys. In alloys with 0, 1, and 2 at.% Co, the only silicide phase is γ(Nb,X)₅Si₃, but in alloys with Co content above 2 at.%, two other types of silicide phases (α(Nb,X)₅Si₃ and β(Nb,X)₅Si₃) also exist except for γ(Nb,X)₅Si₃. Furthermore, Co addition promotes the formation of low-melting-point phases such as Cr₂(Nb,X), Tiss and Ti₂Co between Nbss/γ(Nb,X)₅Si₃ eutectic cells and along the Nbss boundaries, which degrades the compressive strength at 1250 °C of the alloys. However, Co addition increases the nanoindentation hardness of both Nbss and γ(Nb,X)₅Si₃ due to the solid solution strengthening effect of Co. The addition of Co has no significant effect on the oxidation resistance at 1250 °C of the alloys.

5种多元素NbSi基超高温合金，标称成分为Nb-22Ti-14.8Si-4Cr-2.5Al-xCo （x = 0、1、2、4和8 at）。%)通过真空非耗材电弧熔炼制备。研究了Co的加入对合金显微组织、纳米压痕硬度、抗压强度和1250℃等温抗氧化性能的影响。结果表明：随着Co含量的增加，Nbss/γ(Nb，X)5Si3共晶和Nbss相的含量均降低，Co的加入促进了Nbss向枝晶组织转变；同时，Co的加入促进了硅化物相新晶型的形成；Co含量的增加改变了合金的相分数。在具有0、1和2 at的合金中。% Co，唯一的硅化物相是γ(Nb，X)5Si3，但在Co含量大于2 at的合金中。%，除γ(Nb，X)5Si3外，还存在另外两种硅化物相(α（Nb，X)5Si3和β(Nb，X)5Si3）。此外，Co的加入促进了Nbss/γ(Nb，X)5Si3共晶胞间及Nbss晶界上Cr2（Nb，X）、Tiss和Ti2Co等低熔点相的形成，降低了合金在1250℃时的抗压强度。然而，由于Co的固溶强化作用，Co的加入提高了Nbss和γ(Nb，X)5Si3的纳米压痕硬度，而Co的加入对合金在1250℃时的抗氧化性能没有显著影响。

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引用次数: 0

Entropy-driven design of ultra-low loss olivine CaY1–x(Nd0.25Sm0.25Eu0.25Yb0.25)xGaO4 microwave dielectric ceramics for 5 G dielectric resonator antennas 5 G介质谐振器天线用超低损耗绿石CaY1-x (Nd0.25Sm0.25Eu0.25Yb0.25) x高4微波介质陶瓷的熵驱动设计

IF 6.2 2区材料科学 Q1 MATERIALS SCIENCE, CERAMICS

Journal of The European Ceramic Society

Pub Date : 2026-08-01 Epub Date: 2026-02-02 DOI: 10.1016/j.jeurceramsoc.2026.118205

Yang Zhou , Yanling Huang , Qiumei Huang , Ning Guan , Ning Zhang , Huaicheng Xiang , Ying Tang , Liang Fang

Next-generation wireless communication demands microwave dielectric ceramics that effectively achieve ultra-low loss, a stable resonant frequency, and a low permittivity. Here we demonstrate an entropy-engineering strategy that selectively disorders the [A(2)O₆] octahedral site while preserving the rigid [GaO₄] tetrahedral backbone in gallium-based olivine A₂GaO₄. A series of CaY_1–x(Nd_0.25Sm_0.25Eu_0.25Yb_0.25)_xGaO₄ ceramics was synthesized by solid-state reaction at 1260–1420 °C. Systematic increases in configurational entropy (ΔS_config) and ionic-size disorder (δ_R) drive a reversible Pnma → Pmnb symmetry switch, suppress phase separation, and expand the lattice. At x = 0.8, the high-entropy single-phase olivine exhibits ε_r = 9.2 ± 0.2, Q×f = 151,025 ± 400 GHz, and τ_f = -39.8 ± 2.0 ppm/°C, while Vickers hardness rises to 5.79 ± 0.2 GPa. Ultra-low loss is synergistically influenced by ΔS_config, δ_R, and packing fraction. A C-band dielectric resonator antenna fabricated from the x = 0.8 composition achieves 92.63 % radiation efficiency and 6.39 dBi gain, validating the entropy-design paradigm for high-frequency applications.

下一代无线通信要求微波介质陶瓷能够有效地实现超低损耗、稳定的谐振频率和低介电常数。在这里，我们展示了一种熵工程策略，该策略选择性地破坏了镓基橄榄石A2GaO4中的[A(2)O6]八面体位点，同时保留了刚性的[高4]四面体骨架。采用固相反应在1260 ~ 1420℃下合成了一系列CaY1-x (Nd0.25Sm0.25Eu0.25Yb0.25) x高四陶瓷。构型熵（ΔSconfig）和离子尺寸无序（δR）的系统增加驱动了可逆的Pnma→Pmnb对称开关，抑制了相分离，并扩展了晶格。0.8 x = ,熵值单相橄榄石展览εr = 9.2  ±0.2 ,问151025×f =  ± 400 GHz,和τf = -39.8  ± 2.0 ppm /°C,而维氏硬度上升到5.79 ±0.2  GPa。超低损失受ΔSconfig、δR和填料分数的协同影响。由x = 0.8组成的c波段介电谐振器天线实现了92.63 %的辐射效率和6.39 dBi增益，验证了高频应用的熵设计范式。

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引用次数: 0

Synthesis and characterization of REBa2Cu3O7-y superconductors with multiple rare earth elements 含多稀土元素REBa2Cu3O7-y超导体的合成与表征

IF 6.2 2区材料科学 Q1 MATERIALS SCIENCE, CERAMICS

Journal of The European Ceramic Society

Pub Date : 2026-08-01 Epub Date: 2026-02-10 DOI: 10.1016/j.jeurceramsoc.2026.118227

Zerong Zhang , Yanan Wang , Zhan Gao , Xin Liu , Lei Wang , Qiuliang Wang

In this work, five different RE123 samples were prepared via solid-state sintering in flowing air, including (Eu_0.2Gd_0.2Y_0.2Er_0.2Yb_0.2)BCO, (Eu_0.25Gd_0.25Y_0.25Er_0.25)BCO, (Eu_0.33Gd_0.33Y_0.33)BCO, (Nd_0.25Eu_0.25Gd_0.25Y_0.25)BCO and (La_0.2Nd_0.2Y_0.2Er_0.2Yb_0.2)BCO. Their phase constituents, phase stabilities, superconducting properties and microstructures were systematically investigated. Results indicated that RE123 samples with almost pure superconducting phase could be prepared; the superconducting transition temperature (T_c) of each sample was > 90.0 K. The lattice parameters and peritectic decomposition temperature (T_P) increased with the average ionic radius of RE^3 + at the RE site in RE123 samples. The critical current density (J_c) was considerably affected by the constituent elements at the RE site. Specifically, of all samples, (Eu_0.25Gd_0.25Y_0.25Er_0.25)BCO exhibited the highest self-field J_c of 373 kA/_cm² at 4.2 K; this remarkable superconducting performance could be mainly attributed to its higher superconducting volume fraction, but meanwhile, the configuration entropy at the RE site also have contributed to its high J_c value due to the formation of nanoscale SFs.

本文采用流动空气固相烧结法制备了5种不同的RE123样品，分别为（Eu0.2Gd0.2Y0.2Er0.2Yb0.2）BCO、（Eu0.25Gd0.25Y0.25Er0.25）BCO、（Eu0.33Gd0.33Y0.33）BCO、（Nd0.25Eu0.25Gd0.25Y0.25）BCO和（La0.2Nd0.2Y0.2Er0.2Yb0.2）BCO。系统地研究了它们的相组成、相稳定性、超导性能和微观结构。结果表明：可以制备出具有几乎纯超导相的RE123样品；各样品的超导转变温度（Tc）为>； 90.0 K。在RE123样品中，随着RE3 +在RE位点的平均离子半径的增加，晶格参数和包晶分解温度（TP）也随之增加。临界电流密度（Jc）受RE部位组成元素的影响较大。在所有样品中，（Eu0.25Gd0.25Y0.25Er0.25）BCO在4.2 K时表现出373 kA/cm2的最高自场Jc；这种优异的超导性能主要归因于其较高的超导体积分数，但同时，RE位点的组态熵也有助于其高Jc值，这是由于纳米尺度SFs的形成。

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引用次数: 0

High-performance interconnects for high-temperature resistance measurement toward on-line health monitoring of Cf/SiC composites 面向Cf/SiC复合材料在线健康监测的高性能耐高温测量互连

IF 6.2 2区材料科学 Q1 MATERIALS SCIENCE, CERAMICS

Journal of The European Ceramic Society

Pub Date : 2026-08-01 Epub Date: 2026-02-04 DOI: 10.1016/j.jeurceramsoc.2026.118211

Jiawen Song , Haoran Wei , Zhengyuan Shen , Qiang Yang , Ling Xu , Jiahong Niu

In response to the demands for the intelligent thermal structure of aircraft, on-line health monitoring based on high-temperature resistance measurement of ceramic matrix composites (CMCs) can effectively identify the damage state of CMCs. However, highly reliable interconnects between CMCs and metal electrodes remain a major challenge, requiring high temperature resistance, high interface strength and excellent electrical stability. High-performance interconnects were realized by the diffusion reaction of a novel hybrid solder (polysilazane and Ag-Cu-Ti) between Mo electrodes and C_f/SiC composites. Highly conductive and temperature resistant Ti(C,N) and (Ti,Mo)₅Si₃ were formed on the C_f/SiC and Mo electrode side respectively, and a mixed metal/ ceramic structure Ag(C)/Cu/Ti(C,N) were formed in the hybrid solder matrix. The high-performance interconnects exhibit high interface strength of 14.97–19.07 MPa. The resistance measurement can be conducted stably up to 1200 ℃ in an argon atmosphere and 825 ℃ in air with excellent resistance stability and repeatability.

针对飞机智能热结构的需求，基于陶瓷基复合材料高温电阻测量的在线健康监测可以有效识别陶瓷基复合材料的损伤状态。然而，cmc和金属电极之间的高可靠互连仍然是一个主要挑战，需要耐高温、高界面强度和优异的电稳定性。通过一种新型杂化焊料（聚硅氮烷和Ag-Cu-Ti）在Mo电极和Cf/SiC复合材料之间的扩散反应，实现了高性能互连。在Cf/SiC和Mo电极侧分别形成了高导电性和耐温性的Ti（C，N）和（Ti,Mo）5Si3，在杂化钎料基体中形成了混合金属/陶瓷结构Ag(C)/Cu/Ti（C，N）。高性能互连体的界面强度达到14.97 ~ 19.07 MPa。该电阻测量在氩气环境下可稳定测量至1200℃，在空气环境下可测量至825℃，具有良好的电阻稳定性和重复性。

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引用次数: 0

Reaction-controlled effects of (YbxSc1-x)2Si2O7 solid solution against molten calcia-magnesia-aluminosilicate (CMAS) corrosion for environmental barrier coating application （YbxSc1-x）2Si2O7固溶体对环境屏障涂层中熔融钙镁铝硅酸盐（CMAS）腐蚀的反应控制效应

IF 6.2 2区材料科学 Q1 MATERIALS SCIENCE, CERAMICS

Journal of The European Ceramic Society

Pub Date : 2026-08-01 Epub Date: 2026-01-31 DOI: 10.1016/j.jeurceramsoc.2026.118182

Min-Soo Nam , Sahn Nahm , Seongwon Kim

Environmental barrier coatings (EBCs) are essential for protecting SiC_f/SiC ceramic matrix composites from water vapor recession and calcia-magnesia-aluminosilicate (CMAS) corrosion in gas turbines. In this study, (Yb_xSc_1−x)₂Si₂O₇ solid solutions with varying Yb/Sc ratios are evaluated as CMAS-resistant EBC topcoat candidates. Five compositions are synthesized and tested at 1500 °C. Corrosion resistance improves as the optical basicity of the disilicate matches that of CMAS, minimizing chemical reactions and apatite formation; Sc-containing compositions exhibit the best performance. Increasing Sc content decreases the ionic radius and lattice parameters, further inhibiting Ca²⁺ –to–RE³⁺ substitution. Microstructural analysis shows Yb-rich samples retain surface CMAS, whereas Sc-rich samples experience rapid grain-boundary infiltration with less reaction. Thermophysical measurements confirm low, stable thermal conductivity and coefficient of thermal expansion compatibility with SiC_f/SiC substrates. These results indicate that (Yb_xSc_1−x)₂Si₂O₇ solid solutions offer a balanced combination of CMAS corrosion resistance, thermal compatibility, and low thermal conductivity for robust EBCs.

环境屏障涂层（EBCs）是保护SiCf/SiC陶瓷基复合材料免受水蒸气衰退和钙镁铝硅酸盐（CMAS）腐蚀的关键。在这项研究中，具有不同Yb/Sc比率的（YbxSc1−x）2Si2O7固溶体被评估为抗cmas的EBC面漆候选者。合成了五种组合物，并在1500℃下进行了测试。当二硅酸盐的光学碱度与CMAS的光学碱度相匹配时，耐腐蚀性提高，减少了化学反应和磷灰石的形成；含sc的组合物表现出最好的性能。Sc含量的增加降低了离子半径和晶格参数，进一步抑制了Ca2+到re3 +的取代。微观结构分析表明，富钇样品保留了表面CMAS，而富钪样品则经历了快速的晶界渗透，反应较少。热物理测量证实了低，稳定的导热系数和热膨胀系数与SiCf/SiC衬底的相容性。这些结果表明，（YbxSc1−x）2Si2O7固溶体为坚固的EBCs提供了CMAS耐腐蚀性，热相容性和低导热性的平衡组合。

{"title":"Reaction-controlled effects of (YbxSc1-x)2Si2O7 solid solution against molten calcia-magnesia-aluminosilicate (CMAS) corrosion for environmental barrier coating application","authors":"Min-Soo Nam , Sahn Nahm , Seongwon Kim","doi":"10.1016/j.jeurceramsoc.2026.118182","DOIUrl":"10.1016/j.jeurceramsoc.2026.118182","url":null,"abstract":"<div><div>Environmental barrier coatings (EBCs) are essential for protecting SiCf/SiC ceramic matrix composites from water vapor recession and calcia-magnesia-aluminosilicate (CMAS) corrosion in gas turbines. In this study, (YbxSc1−x)2Si2O7 solid solutions with varying Yb/Sc ratios are evaluated as CMAS-resistant EBC topcoat candidates. Five compositions are synthesized and tested at 1500 °C. Corrosion resistance improves as the optical basicity of the disilicate matches that of CMAS, minimizing chemical reactions and apatite formation; Sc-containing compositions exhibit the best performance. Increasing Sc content decreases the ionic radius and lattice parameters, further inhibiting Ca2+ –to–RE3+ substitution. Microstructural analysis shows Yb-rich samples retain surface CMAS, whereas Sc-rich samples experience rapid grain-boundary infiltration with less reaction. Thermophysical measurements confirm low, stable thermal conductivity and coefficient of thermal expansion compatibility with SiCf/SiC substrates. These results indicate that (YbxSc1−x)2Si2O7 solid solutions offer a balanced combination of CMAS corrosion resistance, thermal compatibility, and low thermal conductivity for robust EBCs.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"46 9","pages":"Article 118182"},"PeriodicalIF":6.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146191682","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

Effect of oxygen vacancies at grain boundaries on ferroelastic behavior of yttria stabilized zirconia 晶界氧空位对钇稳定氧化锆铁弹性行为的影响

IF 6.2 2区材料科学 Q1 MATERIALS SCIENCE, CERAMICS

Journal of The European Ceramic Society

Pub Date : 2026-08-01 Epub Date: 2026-01-26 DOI: 10.1016/j.jeurceramsoc.2026.118174

Haoyuan Li , Mohsen Asle Zaeem

This work investigates the role of oxygen vacancies at grain boundaries in governing the ferroelastic behavior of tetragonal prime yttria-stabilized zirconia (t’-YSZ). Using molecular dynamics simulations, ferroelastic domains are induced via quenching and subsequently subjected to mechanical deformation to assess the effects of oxygen vacancy concentration and spatial distribution on domain switching. A Buckingham interatomic potential is employed to capture both t’-YSZ phase formation and ferroelastic domain switching. The results reveal that oxygen vacancy accumulation inhibits domain formation and suppresses ferroelastic reorientation via pinning effects, particularly near grain boundaries. These findings show that grain boundaries act as major sites of oxygen vacancy accumulation, with their structural geometry controlling how vacancies redistribute under compression and tension, thereby directly shaping the ferroelastic switching behavior of t’-YSZ.

本文研究了晶界氧空位在控制四方素数氧化钇稳定氧化锆（t ' -YSZ）铁弹性行为中的作用。利用分子动力学模拟，通过淬火诱导铁弹性畴，随后进行机械变形，以评估氧空位浓度和空间分布对畴切换的影响。利用Buckingham原子间势捕获t′-YSZ相形成和铁弹性畴切换。结果表明，氧空位积累抑制了畴的形成，并通过钉钉效应抑制了铁弹性取向，特别是在晶界附近。这些发现表明晶界是氧空位积累的主要部位，其结构几何形状控制着空位在压缩和拉伸下的重新分布，从而直接塑造了t ' -YSZ的铁弹性开关行为。

引用次数: 0

Potter orientation relationship: The key to the origin of {101¯1} α martensitic twinning and the unusual β precipitation in Zr alloys 波特取向关系：Zr合金中{10.1¯1}α马氏体孪晶和异常β析出的关键

IF 4.6 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

International Journal of Refractory Metals & Hard Materials

Pub Date : 2026-08-01 Epub Date: 2026-02-11 DOI: 10.1016/j.ijrmhm.2026.107730

Xinu Tan , Yushun Liu , Risheng Qiu , Xuan Zhang , Liang Zhang , Jiateng Ma , Wangrui Ren , Feitao Li

Two types of orientation relationship (OR) Burgers and Potter can be observed during the phase transformation between the α and β phases in Zr alloys. In this work, electron back scatter diffraction and high-resolution transmission electron microscopy were carried out to characterize Potter OR in the solution-treated and subsequently annealed Zr alloys. Our results reveal the presence of Potter OR between parent β-Zr and {10

\bar{1}

1}_α twinning Martensite, elucidating the unique variant selection of {10

\bar{1}

1} twins with in a single α-Zr grain in solution-treated samples. Significantly, a novel, non-stress induced, twinning mechanism was proposed via direct phase transformation based on Potter OR in Martensite. Upon annealing, the OR between β-Zr within the twinning Martensite and α-Zr retains Potter OR, independent of the element segregation at twin boundary. The occurrence of Potter OR instead of Burgers OR is attributed to the lower formation energy of Potter OR upon twinning based on our calculation. These results demonstrate an intrinsic association between Potter OR and the formation of {10

\bar{1}

1} twins, shedding light on the designing of novel high-performance Zr alloys.

在Zr合金的α相和β相相变过程中，可以观察到两种取向关系（OR）： Burgers和Potter。在这项工作中，电子背散射衍射和高分辨率透射电镜进行表征波特或在固溶处理和随后退火的Zr合金。我们的研究结果显示亲本β-Zr和{101¯1}α孪晶马氏体之间存在Potter OR，阐明了在溶液处理样品中具有单一α- zr晶粒的{101¯1}孪晶的独特变异选择。值得注意的是，基于马氏体的波特或直接相变，提出了一种新的、非应力诱导的孪生机制。退火后，孪晶马氏体内β-Zr与α-Zr之间的OR保持波特OR，与孪晶边界元素偏析无关。根据我们的计算，波特或而不是汉堡或的出现是由于波特或在孪生时的地层能量较低。这些结果证明了Potter OR与{101¯1}孪晶形成之间的内在联系，为设计新型高性能Zr合金提供了指导。

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引用次数: 0

Microstructure and properties of spark plasma sintered WC–Cu–based in situ composites containing graphite 火花等离子烧结wc - cu基石墨原位复合材料的组织与性能

IF 4.6 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

International Journal of Refractory Metals & Hard Materials

Pub Date : 2026-08-01 Epub Date: 2026-02-05 DOI: 10.1016/j.ijrmhm.2026.107722

Tomila M. Vidyuk , Dina V. Dudina , Alexander I. Gavrilov , Arina V. Ukhina , Vladislav S. Shikalov , Igor S. Batraev , Sergey Yu. Usynin , Boris B. Bokhonov

In this study, in situ WC–Cu–based composites containing graphite were fabricated from a mixture of W, C(graphite) and Cu powders by high-energy mechanical milling and subsequent reactive spark plasma sintering (SPS). The synthesis of the carbides occurred during the SPS stage. In order to investigate the effect of graphite concentration on the structure and properties of the composites, the W–C(graphite)–Cu mixtures with three different molar ratios of elements (1:1:3, 1:1.3:3 and 1:1.7:3) were prepared. The graphite not converted into carbides remained unreacted in the sintered compacts. The combination of mechanical milling and SPS resulted in the formation of unconventional microstructures. The Cu-rich regions of re-solidified material are located between the composite areas, in which the WC and W₂C particles are distributed uniformly. As the concentration of graphite was increased, the hardness and electrical conductivity of the composites decreased. The concentration of graphite in the composites influenced the morphology of the worn surfaces formed under dry sliding conditions. The WC–W₂C–Cu-graphite composite (processing conditions: W–C(graphite)–3Cu mixture, 15 min of milling, SPS at 980 °C) shows an attractive combination of properties: a hardness of 250 HV, an electrical conductivity of 25% of the International Annealed Copper Standard, a residual porosity of less than 5%, a coefficient of friction of 0.58 in a pair with a WC-6Co ball, and a specific wear rate of 0.6 × 10⁻⁵ mm³ N⁻¹ m⁻¹.

在本研究中，将W， C（石墨）和Cu粉末混合，通过高能机械铣削和随后的反应放电等离子烧结（SPS）制备了含有石墨的原位wc - Cu基复合材料。碳化物的合成发生在SPS阶段。为了研究石墨浓度对复合材料结构和性能的影响，制备了三种不同元素摩尔比（1:1:3,1:1.3:3和1:1.7:3）的W-C（石墨）-Cu混合物。未转化为碳化物的石墨在烧结坯中未发生反应。机械铣削与SPS的结合导致了非常规显微组织的形成。再固化材料的富cu区位于复合区之间，其中WC和W2C颗粒分布均匀。随着石墨浓度的增加，复合材料的硬度和电导率下降。复合材料中石墨的浓度影响了干滑动条件下形成的磨损表面的形貌。wc - w2c - cu -石墨复合材料（加工条件：W-C（石墨）-3Cu混合物，铣削15分钟，在980℃下SPS）显示出具有吸引力的性能组合：硬度为250 HV，电导率为国际退火铜标准的25%，残余孔隙率小于5%，与WC-6Co球对的摩擦系数为0.58，比磨损率为0.6 × 10−5 mm3 N−1 m−1。

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引用次数: 0

Corrosion resistance of Yb-silicate materials to molten slag for protective coating applications 用于保护涂层的yb -硅酸盐材料对熔渣的耐腐蚀性

IF 6.2 2区材料科学 Q1 MATERIALS SCIENCE, CERAMICS

Journal of The European Ceramic Society

Pub Date : 2026-08-01 Epub Date: 2026-02-03 DOI: 10.1016/j.jeurceramsoc.2026.118207

Min-Soo Nam , Jin-Kwon Kim , Sahn Nahm , Seongwon Kim

Integrated Gasification Combined Cycle (IGCC) technology offers efficient and cleaner coal-based power generation but introduces corrosion challenges associated with high temperatures and molten slag. This study examines the corrosion behavior of ytterbium monosilicate (Yb₂SiO₅) and its composites containing 5 and 10 wt% Al₂O₃ under IGCC slag conditions. The addition of Al₂O₃ promotes the formation of garnet phases with higher thermal expansion, improving compatibility with the substrate. Samples exposed to molten slag were evaluated for microstructural evolution, thermal expansion, conductivity, and slag resistance. Yb₂SiO₅ exhibited high thermal stability and formed dense protective layers that limited slag infiltration. The composites enhanced thermal compatibility with carbon steel, increasing the coefficient of thermal expansion (CTE) to 9.8 × 10⁻⁶ and 10.9 × 10⁻⁶ K⁻¹ , respectively. The formation of a protective Yb₂Si₂O₇ layer underscores the potential of ytterbium silicates as effective high-temperature coatings for IGCC applications.

综合气化联合循环（IGCC）技术提供了高效、清洁的煤基发电，但也带来了与高温和熔渣相关的腐蚀挑战。本研究研究了单硅酸钇（Yb₂SiO₅）及其含有5和10 wt% Al₂O₃的复合材料在IGCC渣条件下的腐蚀行为。Al₂O₃的加入促进了热膨胀率更高的石榴石相的形成，提高了与基体的相容性。样品暴露于熔渣中，评估其微观结构演变、热膨胀、电导率和抗渣性。Yb₂SiO₅表现出高热稳定性，并形成了致密的保护层，限制了渣的渗透。复合材料增强了与碳钢的热相容性，将热膨胀系数（CTE）分别提高到9.8 × 10⁻⁶和10.9 × 10⁻⁶K⁻¹ 。Yb₂Si₂O₇保护层的形成强调了硅酸钇作为IGCC应用的有效高温涂层的潜力。

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引用次数: 0

Designing extreme-environment ceramics via a dual high-entropy protection strategy 利用双高熵保护策略设计极端环境陶瓷

IF 6.2 2区材料科学 Q1 MATERIALS SCIENCE, CERAMICS

Journal of The European Ceramic Society

Pub Date : 2026-08-01 Epub Date: 2026-02-05 DOI: 10.1016/j.jeurceramsoc.2026.118217

Yang Li , Yueming Li , Xintao Zhang , Xiujuan Chen , Li Tian , Jingjun Xu , Guorui Zhao

The durability of hypersonic structures is limited by catastrophic oxidation of conventional ultra-high temperature ceramics. Here, we investigate the oxidation of a novel high-entropy carbide, (5RE_1/5)Al₃C₃, between 900 and 1300 °C, and reveal a multi-stage protection–failure mechanism that outperforms benchmark carbides. Oxidation begins with a transient amorphous RE–Al–C–O layer, which crystallizes into an ultra-dense nanocrystalline (5RE_1/5)₃Al₅O₁₂/Al₂O₃ scale, forming a robust diffusion barrier. Exceptional stability arises from a dual high-entropy effect: high configurational entropy in both the carbide and its oxide suppresses cation diffusion and arrests grain growth, maintaining protection up to 1200 °C. Even at 1300 °C, a dual-layer scale persists, with eventual linear-kinetic degradation governed by localized destabilization of the amorphous interlayer leading to microporosity, not catastrophic cracking. This work provides the first mechanistic evidence for dual high-entropy protection, establishing a new design principle for oxidation-resistant ceramics.

高超声速结构的耐久性受到传统超高温陶瓷的灾难性氧化的限制。在这里，我们研究了一种新型高熵碳化物（5RE1/5）Al3C3在900 ~ 1300℃之间的氧化，并揭示了一种优于基准碳化物的多级保护失效机制。氧化开始于瞬态无定形RE-Al-C-O层，该层结晶成超致密纳米晶（5RE1/5）3Al5O12/Al2O3尺度，形成坚固的扩散屏障。优异的稳定性源于双重高熵效应：碳化物及其氧化物中的高构型熵抑制阳离子扩散并阻止晶粒生长，在1200°C下保持保护。即使在1300°C时，双层尺度仍然存在，最终的线性动力学降解是由非晶层间的局部不稳定导致的微孔，而不是灾难性的开裂。这项工作为双高熵保护提供了第一个机理证据，建立了一种新的抗氧化陶瓷设计原则。

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引用次数: 0

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