Zhefeng Li , Yu Bai , Jiajing Hao , Hongying Dong , Ting Yang , Yuanming Gao , Wen Ma
{"title":"High-entropy (La0.2Nd0.2Y0.2Yb0.2Lu0.2)2Zr2O7 ceramic: A novel dual-phase high-entropy ceramic","authors":"Zhefeng Li , Yu Bai , Jiajing Hao , Hongying Dong , Ting Yang , Yuanming Gao , Wen Ma","doi":"10.1016/j.jeurceramsoc.2025.117361","DOIUrl":"10.1016/j.jeurceramsoc.2025.117361","url":null,"abstract":"<div><div>Thermal barrier coating (TBC) materials, used to protect high-temperature components in gas turbines, require properties such as low thermal conductivity, resistance to sintering, and high-temperature stability. In this study, a novel defect fluorite-phase high-entropy zirconate powder (La<sub>0.2</sub>Nd<sub>0.2</sub>Y<sub>0.2</sub>Yb<sub>0.2</sub>Lu<sub>0.2</sub>)<sub>2</sub>Zr<sub>2</sub>O<sub>7</sub> was synthesized using solution precursor plasma spraying (SPPS), which exhibits high sphericity and uniform composition distribution. The (La<sub>0.2</sub>Nd<sub>0.2</sub>Y<sub>0.2</sub>Yb<sub>0.2</sub>Lu<sub>0.2</sub>)<sub>2</sub>Zr<sub>2</sub>O<sub>7</sub> ceramic bulk was sintered from SPPS prepared powder by pressureless sintering. The phase structures, thermal and mechanical properties of the samples were investigated using various techniques. The results indicated that the (La<sub>0.2</sub>Nd<sub>0.2</sub>Y<sub>0.2</sub>Yb<sub>0.2</sub>Lu<sub>0.2</sub>)<sub>2</sub>Zr<sub>2</sub>O<sub>7</sub> ceramic bulk has a defect fluorite-pyrochlore dual-phase structure and exhibits a low thermal conductivity about 1.09 W·m⁻¹ ·K⁻¹ at 1400 °C. Compared to La<sub>2</sub>Zr<sub>2</sub>O<sub>7</sub> ceramic, (La<sub>0.2</sub>Nd<sub>0.2</sub>Y<sub>0.2</sub>Yb<sub>0.2</sub>Lu<sub>0.2</sub>)<sub>2</sub>Zr<sub>2</sub>O<sub>7</sub> exhibits a slower grain growth rate of 3.6 × 10⁻⁴ μm/h, it also displays superior mechanical properties, including high hardness (10.03 ± 0.32 GPa) and fracture toughness K<sub>IC</sub> (1.04 ± 0.17 MPa·m¹/²). These outstanding thermal and mechanical properties make (La<sub>0.2</sub>Nd<sub>0.2</sub>Y<sub>0.2</sub>Yb<sub>0.2</sub>Lu<sub>0.2</sub>)<sub>2</sub>Zr<sub>2</sub>O<sub>7</sub> a highly promising candidate for TBC applications.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117361"},"PeriodicalIF":5.8,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143628314","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}
Suk-min Yoon , Babu Madavali , Chul-hee Lee , Rathinam Vasudevan , Hyoung Seop Kim , Soon-Jik Hong
{"title":"Realizing high thermoelectric performance through the synergistic control of intrinsic conduction and enhanced phonon scattering in Cu-doped Bi0.5Sb1.5Te3 alloys","authors":"Suk-min Yoon , Babu Madavali , Chul-hee Lee , Rathinam Vasudevan , Hyoung Seop Kim , Soon-Jik Hong","doi":"10.1016/j.jeurceramsoc.2025.117360","DOIUrl":"10.1016/j.jeurceramsoc.2025.117360","url":null,"abstract":"<div><div>This study explores the use of water-atomization for the mass production of (BiSb)<sub>2</sub>Te<sub>3</sub> powders (∼2Kg/min) with enhanced thermoelectric performance, aimed at large-scale commercial applications. For the first time, excess Cu (0.05 wt%) was incorporated into <em>p</em>-type Bi<sub>0.5</sub>Sb<sub>1.5</sub>Te<sub>3</sub> (BST) alloy using a novel low-impact energy (LIE) process with varying intervals. The BST powders exhibit irregular shapes and bulk crystallites with an R<span><math><mover><mrow><mn>3</mn></mrow><mo>̅</mo></mover></math></span>m rhombohedral structure. The reduction in grain size and the formation of Cu-rich regions at the BST matrix effectively enhanced the phonon scattering in LIE-Cu<sub>0.05</sub>BST alloys. Consequently, the optimized LIE 6h-Cu<sub>0.05</sub>BST exhibited a reduced lattice thermal conductivity of 0.6 W/m. K. at 400 K, along with an improved figure of merit (<em>zT</em>) of 1.2. Furthermore, the spark plasma heat treatment (SPHT) of SPHT-Cu<sub>0.05</sub>BST enhanced electrical conductivity by creating textured grain orientations raising the maximum room-temperature power factor to 4.5<span><math><mo>×</mo></math></span>10<sup>−3</sup> W/m. K<sup>2</sup>, achieving a peak <em>zT</em> of 1.29 at 400 K.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117360"},"PeriodicalIF":5.8,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637673","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}
Zunxing Chu , Chuangming Yang , Jianing Shao , Tiezhu Ma , Tian Xia , Hui Zhao , Qiang Li
{"title":"Developing extraordinary electrocatalytic performance of Fe-based cathode catalysts for solid oxide fuel cells by fluorine doping","authors":"Zunxing Chu , Chuangming Yang , Jianing Shao , Tiezhu Ma , Tian Xia , Hui Zhao , Qiang Li","doi":"10.1016/j.jeurceramsoc.2025.117357","DOIUrl":"10.1016/j.jeurceramsoc.2025.117357","url":null,"abstract":"<div><div>The development of a highly active cathode materials for solid oxide fuel cells (SOFCs) is still a major problem. Herein, we report a fluorine doped Bi<sub>0.8</sub>Ca<sub>0.2</sub>FeO<sub>2.95–<em>δ</em></sub>F<sub>0.05</sub> (BCFF) oxide as promising cathode electrocatalysts for SOFCs. The F doping strategy shows enhanced electrocatalytic activity for the oxygen reduction reaction (ORR) and CO<sub>2</sub> tolerance of the Bi<sub>0.8</sub>Ca<sub>0.2</sub>FeO<sub>3–<em>δ</em></sub> cathode. BCFF cathode possesses the excellent electrochemical performance, as evidenced by a lower polarization resistance of 0.07 Ω cm<sup>2</sup> at 700 ℃. The single cell delivers a maximum power density of 826, 978, and 1260 mW cm<sup>−2</sup> at 700, 750 and 800 ℃, respectively. This enhanced ORR activity is due to the fact that the high electronegativity of F indirectly adjusts the electron density of adjacent O atoms, enabling BCF to release more lattice oxygen and provide more oxygen vacancies. This study provides an effective strategy for the development of the cathode catalysts for SOFCs.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117357"},"PeriodicalIF":5.8,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592153","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}
Xunxun Hu , Yongguo Chen , Jian He , Hongbo Guo , Shengkai Gong , Huibin Xu
{"title":"YPO4: A promising environmental barrier coating candidate against corrosion of molten CMAS","authors":"Xunxun Hu , Yongguo Chen , Jian He , Hongbo Guo , Shengkai Gong , Huibin Xu","doi":"10.1016/j.jeurceramsoc.2025.117359","DOIUrl":"10.1016/j.jeurceramsoc.2025.117359","url":null,"abstract":"<div><div>Calcium-magnesium-alumina-silicate (CMAS) attack is one of the major challenges for environmental barrier coatings (EBCs) applied on the hot-sections of silicon carbide based ceramic matrix composites (CMCs) in aero-engines. YPO<sub>4</sub> is a promising EBC candidate owing to its coefficient of thermal expansion (CTE) compatibility with CMC<sub>S</sub> and superior corrosion resistance to water vapor. In this work, single phase YPO<sub>4</sub> ceramic was successfully fabricated and its corrosion-resistance to synthesized CMAS and natural volcanic ash at 1300–1400 °C was investigated. At 1300 °C, the chemical reaction between YPO<sub>4</sub> ceramics and molten CMAS accelerated, forming a continuous and dense reaction layer composed of Ca<sub>8</sub>MgY(PO<sub>4</sub>)<sub>7</sub> and Ca<sub>6</sub>MgY<sub>3</sub>(SiO<sub>4</sub>)<sub>2</sub>(PO<sub>4</sub>)<sub>5</sub> phases, thereby effectively inhibiting CMAS infiltration. With the increase in corrosion time, the reaction layer thickness follows a near-parabolic trend. At temperatures above 1300 °C, the formation of the reaction layer was constrained due to the extremely low viscosity of CMAS and its fast infiltration rate. In contrast to CMAS, volcanic ash did not react with YPO<sub>4</sub> ceramic at high temperature due to its relatively low CaO content. These findings are expected to provide comprehensive understanding on the corrosion performance and mechanism of REPO<sub>4</sub> coating materials.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117359"},"PeriodicalIF":5.8,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592154","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}
Bettina Osswald , Lenka Müller , Janet Grabow , Frank A. Müller , Frank Kern
{"title":"Evaluation of 1.5 mol% yttria – 1.5 mol% gadolinia stabilized tetragonal zirconia polycrystals derived from solid state synthesis and laser vaporation","authors":"Bettina Osswald , Lenka Müller , Janet Grabow , Frank A. Müller , Frank Kern","doi":"10.1016/j.jeurceramsoc.2025.117345","DOIUrl":"10.1016/j.jeurceramsoc.2025.117345","url":null,"abstract":"<div><div>Variation of stabilizer composition and amount offers the opportunity to tailor the mechanical properties of tetragonal zirconia polycrystals. In this study, zirconia stabilized with 1.5 mol% yttria and 1.5 mol% gadolinia was prepared by co-milling zirconia with yttria and gadolinia stabilizer oxides. A laser vaporized powder was derived from this starting powder. The two powders were subsequently consolidated into bulk ceramics by hot pressing at 1300–1450 °C sintering temperature and 60 MPa pressure. Tetragonal zirconia polycrystals obtained from the different powder technology processes differ considerably in phase composition, microstructure and mechanical properties. The laser vaporized derived materials are predominantly tetragonal, hard and combine high strength with a moderate toughness. The solid state synthesized materials show a transition to higher hardness and strength and lower fracture resistance with increasing sintering temperature, which can be correlated to the changes in phase composition and microstructure.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117345"},"PeriodicalIF":5.8,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chenchen Qi , Xiaojian Ji , Jingjing Li , Zhanming Hu , Xuemin Wei , Bo Xiao , Mingchao Wang
{"title":"The preparation and performance analysis of high-entropy phosphate high-temperature resistant adhesives","authors":"Chenchen Qi , Xiaojian Ji , Jingjing Li , Zhanming Hu , Xuemin Wei , Bo Xiao , Mingchao Wang","doi":"10.1016/j.jeurceramsoc.2025.117356","DOIUrl":"10.1016/j.jeurceramsoc.2025.117356","url":null,"abstract":"<div><div>In response to the weak bonding effect caused by the difference in thermal expansion between aluminum phosphate adhesive and alumina, a series of high-entropy phosphate adhesives (8.9 ×10<sup>−1</sup> K<sup>−1</sup>) with high thermal expansion matching to alumina (9 ×10<sup>−6</sup> K<sup>−1</sup>) were developed and analyzed. The adhesive could cure at room temperature and evolve into a stable high-entropy ceramic structure during heat treatment. Among them, (La<sub>0.2</sub>Ce<sub>0.2</sub>Sm<sub>0.2</sub>Nd<sub>0.2</sub>Eu<sub>0.2</sub>)PO<sub>4</sub> adhesive showed the best bonding performance since the generation of high-entropy ceramic. Without adding other additives, it provided a bonding strength of 14.8 MPa for alumina, 74 times that of aluminum phosphate. The strength retention rate remained at 40 % after 20 thermal cycles from room temperature to 1500 °C. The adhesion mechanism relied on the combination of mechanical interlocking, chemical bond adhesion and electrostatic interactions, and reinforced by the four core effects of high-entropy structure. High-entropy adhesives showed great prospects in aerospace, electronics, medical, and other fields.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117356"},"PeriodicalIF":5.8,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Applying archaeomagnetic methods to virtually reconstruct medieval pavements: Insights from Tiebas Castle (Spain)","authors":"Iván Ruiz-Ardanaz , Esther Lasheras , Adrián Durán","doi":"10.1016/j.jeurceramsoc.2025.117344","DOIUrl":"10.1016/j.jeurceramsoc.2025.117344","url":null,"abstract":"<div><div>Archaeomagnetic dating is commonly applied to baked clay materials. Through these methods, the chronology is calculated by analysing the material's remanent magnetism and knowing its original position. Here, the reverse approach was applied: knowing the chronology and remaining magnetism, the original orientation was virtually reconstructed. This reverse method was tested on some tiles from Tiebas Castle (Spain) proving novel insights of its pavements. The object of analysis was a set of tiles that had been heated twice: first during their manufacture in the mid-13th century, and after, during the castle destruction by a fire in 1378, when they were part of the pavement. Through these results it was determined which halls were covered with tiles and to estimate their original orientation in them. Additionally, it has been possible to estimate the temperatures reached during the fire (240–540 ºC). This novel application demonstrates potential for broader use in reconstructing archaeological ceramic structures like kilns, ovens, or pottery.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117344"},"PeriodicalIF":5.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592152","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}
Antonio Vinci, Matteo Mor, Simone Failla, Pietro Galizia, Luca Zoli, Diletta Sciti
{"title":"Novel CMCs based on B4C-TiB2 blends and carbon fibres","authors":"Antonio Vinci, Matteo Mor, Simone Failla, Pietro Galizia, Luca Zoli, Diletta Sciti","doi":"10.1016/j.jeurceramsoc.2025.117355","DOIUrl":"10.1016/j.jeurceramsoc.2025.117355","url":null,"abstract":"<div><div>Lightweight carbon fibre reinforced B<sub>4</sub>C/TiB<sub>2</sub> composites with varying B<sub>4</sub>C contents and fibre gradients were produced by slurry infiltration and sintering for the first time. Tuning the B<sub>4</sub>C content allowed to adjust the fibre/matrix interfacial strength, leading to different fracture behaviours: for a B<sub>4</sub>C content of 75 %, the fibre/matrix interface was relatively weak and the composite had significantly high fracture toughness, whereas higher TiB<sub>2</sub> contents led to a denser matrix, stronger interface and low degree of delamination. Even though the fracture toughness was considerably high, the addition of Carbon fibres lowered the hardness down to ≈ 4 GPa. Therefore, an additional composite with a fibre gradient was fabricated to demonstrate the feasibility of combining a high fibre content in the inner layer with a harder layer on the outside, reaching hardness values of ≈ 27 GPa.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117355"},"PeriodicalIF":5.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kaifei Fan, Hongkang Ou, Xuemeng Zhang, Jia Sun, Hejun Li
{"title":"Long term durability against water vapor corrosion at 1500 °C for environmental barrier coating modified by alumina","authors":"Kaifei Fan, Hongkang Ou, Xuemeng Zhang, Jia Sun, Hejun Li","doi":"10.1016/j.jeurceramsoc.2025.117354","DOIUrl":"10.1016/j.jeurceramsoc.2025.117354","url":null,"abstract":"<div><div>Advanced aero-engine have made environmental barrier coatings work in an increasingly harsh service atmosphere. In this work, the water-vapor corrosion behaviors up to 200 h at 1500 °C of Yb<sub>2</sub>Si<sub>2</sub>O<sub>7</sub>-Al<sub>2</sub>O<sub>3</sub> coatings prepared using core-shell structured powders were explored. Results showed that the Al<sub>2</sub>O<sub>3</sub> shell hindered the deposition of Yb<sub>2</sub>SiO<sub>5</sub> secondary phase in the sprayed coating due to the low vapor partial pressure of substances containing Al. During corrosion, the <em>in-situ</em> consumption of Al<sub>2</sub>O<sub>3</sub> in the coating actualized the premature decrease of Yb<sub>2</sub>SiO<sub>5</sub>, and generated the aluminosilicate, ultimately reducing the maximus tensile stress by about 32 %. Moreover, the external diffusion of Al, activated the formation of protective Yb<sub>3</sub>Al<sub>5</sub>O<sub>12</sub> reaction layer, instead of porous Yb<sub>2</sub>SiO<sub>5</sub> layer on Yb<sub>2</sub>Si<sub>2</sub>O<sub>7</sub>-Al<sub>2</sub>O<sub>3</sub> coating, achieving a lower mass loss than the pristine Yb<sub>2</sub>Si<sub>2</sub>O<sub>7</sub> coating, indicating an improved durability of Yb<sub>2</sub>Si<sub>2</sub>O<sub>7</sub>-Al<sub>2</sub>O<sub>3</sub> coating.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117354"},"PeriodicalIF":5.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637672","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}
Emilija Nidžović , Branko Matović , Peter Tatarko , Naser Hosseini , Ondrej Hanzel , Zdeněk Chlup , Stevan Dimitrijević , Lidija Radovanović , Aleksandra Dapčević , Marija Prekajski Đorđević
{"title":"High-entropy spinel oxides: Self-propagating synthesis and densification by spark plasma sintering","authors":"Emilija Nidžović , Branko Matović , Peter Tatarko , Naser Hosseini , Ondrej Hanzel , Zdeněk Chlup , Stevan Dimitrijević , Lidija Radovanović , Aleksandra Dapčević , Marija Prekajski Đorđević","doi":"10.1016/j.jeurceramsoc.2025.117353","DOIUrl":"10.1016/j.jeurceramsoc.2025.117353","url":null,"abstract":"<div><div>The self-propagating room temperature method was utilized to synthesize high-entropy spinel oxides (HESOs): (Co,Cr,Fe,Mn,Ni)<sub>3</sub>O<sub>4-δ</sub>, (Mg,Cr,Fe,Mn,Ni)<sub>3</sub>O<sub>4-δ</sub>, (Mg,Co,Fe,Cr,Mn)<sub>3</sub>O<sub>4-δ</sub>, (Mn,Zn,Fe,Ni,Cr)<sub>3</sub>O<sub>4-δ</sub>, and (Co,Mn,Zn,Fe,Cr)<sub>3</sub>O<sub>4-δ</sub>. After thermal treatment at 1000 °C, XRD analysis confirmed their single-phased spinel<span><math><mrow><mspace></mspace><mo>(</mo><mi>Fd</mi><mover><mrow><mn>3</mn></mrow><mo>¯</mo></mover><mi>m</mi><mo>)</mo></mrow></math></span> structure. Densification by spark plasma sintering was successfully used for the first time on HESOs, resulting in relative densities from 94 % to 99 % while retaining the spinel structure. SEM/EDS mapping displayed a homogenous, dense microstructure with minimal porosity. (Mn,Zn,Fe,Ni,Cr)<sub>3</sub>O<sub>4-δ</sub> displayed the highest bending strength (171.5 MPa) and Young’s modulus (188 GPa). (Mg,Co,Fe,Cr<sub>,</sub>Mn)<sub>3</sub>O<sub>4-δ</sub> demonstrated the highest hardness (8.8 GPa), while (Mg,Cr,Fe,Mn,Ni)<sub>3</sub>O<sub>4-δ</sub> exhibited the highest indentation fracture toughness (1.5 MPa m<sup>–1/2</sup>). The lowest thermal diffusivity (0.67 – 0.51 mm<sup>2</sup> s<sup>–1</sup>) was recorded for (Co,Mn,Zn,Fe,Cr)<sub>3</sub>O<sub>4-δ</sub>, while (Co,Cr,Fe,Mn,Ni)<sub>3</sub>O<sub>4-δ</sub>, had the highest thermal diffusivity (0.82 – 0.58 mm<sup>2</sup> s<sup>–1</sup>). The study demonstrated a simple and efficacious method of synthesizing and densifying HESOs with structural, mechanical, and thermal properties favourable for different applications.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 10","pages":"Article 117353"},"PeriodicalIF":5.8,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562593","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}