Ceramics International最新文献

{"title":"Synthesis and spectroscopic analysis in KYF4: Ce3+/Gd3+: A UV emitting phosphor synthesized by solid state metathesis","authors":"Nilesh S. Ugemuge ,&nbsp;Shruti P. Dhale ,&nbsp;Vartika S. Singh ,&nbsp;S.V. Moharil","doi":"10.1016/j.ceramint.2025.06.256","DOIUrl":"10.1016/j.ceramint.2025.06.256","url":null,"abstract":"<div><div>Synthesis of KYF₄<span><span> by solid state metathesis is reported. XRD results indicated almost </span>pure cubic phase with some weak lines of hexagonal phases. Luminescence of Ce</span>³⁺, on the other hand, showed presence of Ce³⁺<span> centres in both cubic and hexagonal phases. Luminescence spectra<span> in two phases differ. Emission in the cubic phase lies at longer wavelengths as compared to that in the hexagonal phase. The difference is attributed to the weaker crystal field in the hexagonal phase. Two phase structure was not reflected in the luminescence of Gd</span></span>³⁺. Gd³⁺ luminescence originates in f-f transitions which are less sensitive to the structural changes as compared to the f-d transitions of Ce³⁺. These results can explain the inconsistencies in the literature reports on Ce³⁺ luminescence in KYF₄. These investigations also furnish a fast method for preparing KYF₄ based phosphors.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 40234-40243"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922681","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":"Dielectric properties of Sm2GeO5 ceramics at microwave frequencies and their influencing factors","authors":"Yuan Nie,&nbsp;Yanjun Liu,&nbsp;Ziqi Zhao,&nbsp;Wenjie Zhang,&nbsp;Weilin Chen,&nbsp;Mengyao Wang,&nbsp;Fangyi Huang,&nbsp;Xiuli Chen,&nbsp;Huanfu Zhou","doi":"10.1016/j.ceramint.2025.06.227","DOIUrl":"10.1016/j.ceramint.2025.06.227","url":null,"abstract":"<div><div>In this study, low-permittivity Sm₂GeO₅<span><span> ceramics were synthesized via solid-state reaction. XRD and </span>Rietveld refinement confirmed a monoclinic crystal structure (space group </span><em>P</em>2₁/<em>c</em><span>). SEM was employed to analyze grain growth. The microwave dielectric properties<span> were systematically investigated, revealing that the void ratio critically influences the dielectric constant of the samples. The </span></span><em>Q×f</em> values of the ceramics exhibited a strong dependence on the void fraction, packing fraction, and lattice energy. Meanwhile, the valence state of B-site cations played a critical role in determining the temperature stability. When sintered at 1400 °C, the ceramics achieved a high relative density of 95.74 %, further supporting their optimized microwave dielectric performance. Excellent microwave dielectric properties were achieved: <em>ε</em>_<em>r</em> = 13.72, <em>Q×f</em> = 43723 GHz, <em>τ</em>_<em>f</em> = −84.21 ppm/°C. This study provides a comprehensive analysis of the key factors influencing the microwave dielectric properties of Sm₂GeO₅ ceramics. The excellent microwave dielectric properties of Sm₂GeO₅ ceramics indicate that they have promising applications in radar, mobile communication base stations, and satellite navigation.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 39946-39952"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922856","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":"Effect of shear rate on the rheological and crystallization behaviors of CaO-SiO2-CaF2-Ce2O3 slag melt at high temperature","authors":"Wentao Guo ,&nbsp;Xi Lan ,&nbsp;Yongli Jin ,&nbsp;Ziqi Ding ,&nbsp;Jintao Gao ,&nbsp;Zhancheng Guo ,&nbsp;Zengwu Zhao","doi":"10.1016/j.ceramint.2025.06.228","DOIUrl":"10.1016/j.ceramint.2025.06.228","url":null,"abstract":"<div><div><span>The irreplaceability role of rare earths in high-performance materials, such as ceramics, highlighting the significance of rare earth extraction<span><span>. Strengthening the crystallization growth of the rare earth phase in rare earth slag is crucial for ensuring effective subsequent rare earth enrichment and separation. However, viscosity plays a major role in the characteristics of high-temperature melts and the </span>crystallization process. In this study, an internal column rotation method was used to measure the viscosity of CaO-SiO</span></span>₂-CaF₂-Ce₂O₃<span> slag melts. The effect of shear rate on the rheological behavior of CaO-SiO</span>₂-CaF₂-Ce₂O₃ slag with varying Ce₂O₃ and CaF₂ contents, and CaO/SiO₂ ratio was investigated by examining the viscosity evolution during the rare earth crystallization growth process. The rheological behavior of the CaO-SiO₂-CaF₂-Ce₂O₃<span> slag was elucidated in regions of liquid phase, low solid phase, and high solid phase, providing insight into the viscosity changes of non-Newtonian flowing melts. Based on this, the effect of shear rate on the crystallization behavior of rare earth phases was investigated to provide a basis for improving the subsequent separation of rare earth phases.</span></div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 39953-39961"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922857","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":"Effect of V5+/V4+ substitution on structural and magnetic orderings of SrFeO3-δ","authors":"Rakhi Saha ,&nbsp;Koyal Suman Samantaray ,&nbsp;P. Maneesha ,&nbsp;Suresh Chandra Baral ,&nbsp;Sachindra Nath Sarangi ,&nbsp;Rajashri Urkude ,&nbsp;Biplab Ghosh ,&nbsp;R. Mittal ,&nbsp;Mayanak K. Gupta ,&nbsp;Abdelkarim Mekki ,&nbsp;Khalil Harrabi ,&nbsp;Somaditya Sen","doi":"10.1016/j.ceramint.2025.06.220","DOIUrl":"10.1016/j.ceramint.2025.06.220","url":null,"abstract":"<div><div>SrFeO_3-δ<span><span> is a structurally versatile material, showing cubic (C) symmetry at δ = 0, which transitions to tetragonal (T) and then orthorhombic (Or) with increasing oxygen vacancies. These structural changes alter magnetic behavior through variations in bond angles and lengths, enabling both </span>antiferromagnetic (AFM) and ferromagnetic (FM) interactions between Fe</span>⁴⁺/Fe³⁺<span> ions and oxygen (or vacancies). While such tunable magnetic phases offer rich physics and potential applications, achieving room-temperature (RT) FM remains challenging. This study explores V</span>⁵⁺/V⁴⁺ doping in SrFeO_3-δ (SrFe_1-xV_xO_3-δ<span><span>; 0 ≤ x ≤ 0.03) to induce FM persisting up to RT and investigates its structural-magnetic correlation. Structural analysis from X-ray diffraction (XRD) and Raman spectroscopy, supported by </span>phonon mode calculations, reveals that SrFeO</span>_3-δ<span><span><span> is in a mixed T-Or phase. At the same time, V-doped samples exhibit an emerging C-phase in a dominant T-lattice. Magnetic hysteresis (M − H) loops show notable FM behavior within the AFM matrix at low temperature ∼10K, with a FM and paramagnetic phase at </span>room temperature. Temperature-dependent magnetization measurements indicate a T-phase related </span>Néel temperature (</span><em>T</em>_<em>N</em><span>) shift from 70K to 55K in the doped samples as compared to the pure<span> one. An increased magnetization difference between the field-cooled (FC) and zero-field-cooled (ZFC) data with increasing V-content suggests an increasing magnetic frustration due to competing FM/AFM exchange interactions. X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge structure (XANES) analyses reveal a rise in Fe</span></span>³⁺ and V⁵⁺<span> states, affecting oxygen vacancy distributions and corresponding structural shifts seen in XRD and Raman results. The multivalent Fe</span>³⁺/Fe⁴⁺ and V⁴⁺/V⁵⁺ states enhance Double-Exchange (DE) interactions (Fe³⁺-O-Fe⁴⁺ and Fe³⁺-O-V⁵⁺), and V_O-mediated Fe³⁺-V_O-Fe³⁺<span> interaction, promoting ferromagnetism. Moreover, frequency-dependent magnetization studies display a subtle susceptibility peak shift, indicating spin-glass-like behavior in V-doped samples.</span></div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 39855-39865"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922928","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":"Fabrication of Li4SiO4@Li2TiO3 core-shell tritium breeding materials with controlled thickness and improved moisture stability via a shrinkage matching process","authors":"Ruichong Chen ,&nbsp;Leiqing Tang ,&nbsp;Yi Zuo ,&nbsp;Jianqi Qi ,&nbsp;Wei Feng ,&nbsp;Haomin Wang ,&nbsp;Zhangyi Huang ,&nbsp;Tiecheng Lu","doi":"10.1016/j.ceramint.2025.06.215","DOIUrl":"10.1016/j.ceramint.2025.06.215","url":null,"abstract":"<div><div>In this study, a shrinkage matching process was developed to achieve synchronous shrinkage of Li₄SiO₄ and Li₂TiO₃<span> during sintering, enabling the successful fabrication of a core-shell structured tritium breeder material with a Li</span>₄SiO₄ core and Li₂TiO₃<span> shell to address the hygroscopicity of Li</span>₄SiO₄. The shell thickness of the Li₄SiO₄@Li₂TiO₃<span><span> core-shell breeding materials can be controlled in the range of 0–235 μm, and their moisture stability was systematically investigated at 10 % RH, 50 % RH, and 80 % RH. Results showed that increasing shell thickness significantly enhanced phase and mechanical stability in </span>humid environments, although excessively thick shells reduced overall Li content. To understand these improvements, the moisture stabilization mechanism of this core-shell breeding ceramics was comprehensively analyzed. Notably, the core-shell pebbles with a shell thickness of 146 μm exhibited a satisfactory crushing load (80.5 N) and a suitable Li content (16.87 wt%), and maintained superior moisture stability after storage at 80 % RH for 14 days. This novel concept, preparation route, and elucidated mechanism of utilizing Li</span>₂TiO₃ shell to enhance the moisture stability of Li₄SiO₄<span> matrix provide a new strategy for performance enhancement of advanced tritium breeding materials.</span></div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 39801-39811"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144921159","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":"In-situ low-temperature synthesis of mullite whiskers from MoO3-doped industrial silica-alumina waste and growth kinetics study","authors":"Weilong Chen ,&nbsp;Xiaohua Gu ,&nbsp;Anyu Fan ,&nbsp;Heng Li ,&nbsp;Qingyong Su","doi":"10.1016/j.ceramint.2025.06.185","DOIUrl":"10.1016/j.ceramint.2025.06.185","url":null,"abstract":"<div><div><span>This study employed industrial silica-alumina waste residue as the principal raw material, achieving low-temperature synthesis of mullite whiskers through Al(OH)</span>₃ supplementation for silica-alumina ratio adjustment, with MoO₃<span><span> as the sole sintering aid<span>. An innovative conceptual design for exhaust gases recovery system was developed. The critical controlling factors and kinetic mechanisms governing whisker growth during low-temperature sintering were systematically investigated. Combined characterization techniques of X-ray diffraction analysis and scanning electron microscopy were employed to comprehensively analyze phase evolution patterns and </span></span>microstructural characteristics. Experimental optimization determined the optimal temperature range for whisker growth and the optimum MoO</span>₃<span><span><span> doping concentration. A physical model for whiskers agglomeration growth was established with corresponding formation mechanisms elucidated. Based on crystal growth theory and Arrhenius equation, </span>growth kinetic parameters along different </span>crystallographic orientations<span> were quantitatively characterized, with apparent activation energies calculated. Results demonstrated that MoO</span></span>₃<span> doping content significantly influenced phase purity and crystal morphology<span>, with excessive doping (&gt;7 wt%) inhibiting mullite crystal growth. Notably, MoO</span></span>₃<span><span> catalysis enabled mullite nucleation temperature reduction to 700 °C, with stable crystallization temperature range maintained at 800–850 °C. The doped system induced markedly </span>anisotropic<span> growth characteristics in mullite whiskers, resulting in a maximum whisker length of 12 μm and an aspect ratio of 11. At 850 °C, longitudinal growth activation energies measured 306.5, 184.8, and 229.5 kJ/mol for 4 wt%, 7 wt%, and 10 wt% MoO</span></span>₃<span> doping levels respectively, while transverse activation energies correspondingly reached 490.6, 658.7, and 671.6 kJ/mol. The activation energy differences confirmed the intrinsic crystallographic orientation-selective growth characteristics, highlighting the dual advantages of this process in low-temperature energy conservation and solid waste resource utilization.</span></div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 39498-39510"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922243","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":"Enhanced energy storage density and efficiency in A/B-site-engineered silver niobate ceramics","authors":"Renzhong Xue ,&nbsp;Xiaosong Liu ,&nbsp;Yuping Yang ,&nbsp;Xiang Zhu ,&nbsp;Haiyan Wang","doi":"10.1016/j.ceramint.2025.06.190","DOIUrl":"10.1016/j.ceramint.2025.06.190","url":null,"abstract":"<div><div><span>Lead-free silver niobate (AgNbO</span>₃, AN) ceramics have great potential in the pulse power equipment and other application fields due to fast charge and discharge speeds and high power density. However, their inferior energy storage density and efficiency limit their application. To address these issues, the cooperative optimization of A/B-sites in AN ceramics through Sm³⁺, Ca²⁺ and Ta⁵⁺ co-doping was performed in the present work. Such modification strategy inhibited the grain growth, while promoting the formation of a room-temperature M₂-M₃<span> phase boundary, enhancing the antiferroelectric stability and relaxation feature. The breakdown field strength increased from 210 kV/cm for AN to 394 kV/cm for Ag</span>_0.75Sm_0.05Ca_0.05Nb_0.9Ta_0.1O₃ ceramic. As a result, an ultrahigh energy storage density of 7.16 J/cm³ and a high efficiency of 81.2 % at 385 kV/cm along with excellent frequency, temperature and cycle stabilities were achieved in Ag_0.8Sm_0.04Ca_0.04Nb_0.9Ta_0.1O₃ ceramics. Therefore, this study demonstrates the effectiveness of comprehensive regulation of AN energy storage performance and its applicability for modern electrical and electronic equipment.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 39549-39557"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922248","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":"High thermoelectric performance in (Ga, Yb) Co-doped Bi2S3 bulks achieved by band structure and carrier concentration modulation","authors":"Ze-Yuan Yang,&nbsp;Qiu-Yu Luo,&nbsp;Chong-Yu Wang,&nbsp;Yang-Wei Wang,&nbsp;Jiang-Hu Yu,&nbsp;Xi Yan,&nbsp;Yi-Xin Zhang,&nbsp;Xing Yang,&nbsp;Jing Feng,&nbsp;Zhen-Hua Ge","doi":"10.1016/j.ceramint.2025.06.218","DOIUrl":"10.1016/j.ceramint.2025.06.218","url":null,"abstract":"<div><div>Due to their high abundance, low cost, and low toxicity, Bi₂S₃<span>-based thermoelectric materials without Te are significantly promising for eco-friendly and scalable applications. However, the ZT value of Bi</span>₂S₃<span>-based is not high enough and must be further improved. The rare-earth element doping is a promising strategy for synergistically enhancing the electrical and thermal transport properties. This study selected GaTe and YbBr</span>₃ for co-doping in Bi₂S₃<span><span> polycrystals<span><span> using a solid-state reaction and spark plasma sintering<span>, which enabled simultaneous modulation of the band structure and carrier concentration for significantly enhanced </span></span>thermoelectric and mechanical properties. Specifically, the synergistic optimization of electrical and </span></span>phonon transport was initially achieved through GaTe doping in Bi</span>₂S₃<span>, which effectively reduced the lattice thermal conductivity<span> while enhancing electrical conductivity. However, the improvement in thermoelectric performance with GaTe doping alone remained limited. Br substituted S to introduce extra electrons, while Yb replaced Bi to reduce the bandgap from 1.38 to 1.05 eV. The two effects synergistically optimized the electrical transport properties of the matrix. As a result, the optimized Bi</span></span>₂S₃ + 0.5 wt% GaTe +1.0 wt% YbBr₃ sample achieved an exceptional average power factor of 475.4 μW m⁻¹ K⁻²<span> over 323–773 K. Additionally, point defects<span><span>, dislocations, and micropores induced by the second phase contributed to strong phonon scattering, leading to a low lattice </span>thermal conductivity of 0.56 W m</span></span>⁻¹ K⁻¹ at 773 K. Consequently, a peak <em>ZT</em> value of 0.67 at 773 K and a high average <em>ZT</em> value of 0.45 over 323–773 K were achieved, which were relatively higher than other values reported in the literature. Furthermore, the mechanical properties were improved, with hardness increasing from 2.55 to 2.93 GPa, making Bi₂S₃ more deformation-resistant and durable. This study showed that co-doping rare earth elements was an effective approach for enhancing the thermoelectric and mechanical properties of the Bi₂S₃ material.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 39833-39842"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922578","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":"Enhanced thermoelectric properties of spark plasma sintered SiC with in-situ TiB2 network structures","authors":"Salih Cagri Ozer","doi":"10.1016/j.ceramint.2025.06.235","DOIUrl":"10.1016/j.ceramint.2025.06.235","url":null,"abstract":"<div><div>SiC-based composites with in-situ TiB₂ network structures were produced by coating mechanically alloyed B₄<span><span>C-TiC particle mixtures on SiC granules, and then utilizing the spark plasma sintering<span> process to obtain bulk composites with improved thermoelectric properties. A high amount of electrically conductive secondary phase introduction is generally necessary to improve the electrical transport properties of SiC, which causes adverse effects on the Seebeck coefficient and </span></span>thermal conductivity. Instead, producing a network structure of TiB</span>₂ on SiC, rather than a SiC-TiB₂<span> particulate composite<span> approach, was found to be effective in enhancing the electrical and thermal conductivity of SiC, with a minimum amount of secondary phase formation. The effects of different amounts of in-situ TiB</span></span>₂ network on the temperature-dependent electrical and thermal transport properties of SiC were analyzed. Increasing amounts of TiB₂ formation resulted in simultaneously increased electrical and decreased thermal conductivities by the conductive network and increased phonon scattering, respectively. Although the Seebeck coefficients of the final composites ultimately reduced due to the metallic nature of the in-situ TiB₂ network, optimizing the composition revealed a high thermoelectric performance at high temperatures. The dimensionless figure of merit value peaked at 2.5 vol% TiB₂ content as 8.5 × 10⁻³ at 923 K, which is approximately 210 % higher than monolithic SiC.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 40022-40031"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922803","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":"Wettability and interfacial reaction of ZrO2 and Y2O3 doped Al2O3-based ceramic shells in K417G superalloy investment casting","authors":"Baohong Kou ,&nbsp;Wentao Zhou ,&nbsp;Yujie Lin ,&nbsp;Fei Han ,&nbsp;Jing Ouyang","doi":"10.1016/j.ceramint.2025.06.243","DOIUrl":"10.1016/j.ceramint.2025.06.243","url":null,"abstract":"<div><div>Interfacial reactions between K417G Ni-based superalloy and Al₂O₃<span>-based ceramic shells during investment casting negatively impact the surface quality of the resulting castings. To mitigate this issue, ZrO</span>₂ and Y₂O₃<span> were introduced to modify the microstructure, phase composition, and chemical properties of the shell surface. The effects of dopant<span> type and content (2–5–8 wt%) on interfacial reactions and wettability were systematically investigated using the sessile-drop method. The reaction products were characterized to understand the underlying mechanisms. The results show that increasing the ZrO</span></span>₂ content reduced the surface porosity and roughness of the shell. During sintering (950 °C, 2 h), the dopants reacted with SiO₂ to form silicates (Y₂SiO₅ and ZrSiO₄<span>), thereby enhancing the thermal stability of the shell. Under interfacial reaction conditions (1350 °C, 40 min), increasing the dopant content (2–5 wt%) significantly improved the alloy surface quality, reducing sand sticking defects, exposing more of the alloy matrix, and increasing the alloy-shell contact angle. However, at an 8 wt% dopant content, part of the dopant reacted with the Al</span>₂O₃ layer on the alloy surface, forming Al₂O₃·ZrO₂ and Al₂O₃·Y₂O₃<span> composite oxides. These reactions intensified localized interactions, resulting in the formation of ‘special reaction pits’, which ultimately reduced both the alloy surface quality and the alloy-shell contact angle. These findings suggest that the compositional design of Al</span>₂O₃-based ceramic shells promotes the formation of silicates, enhances thermal stability of the shell materials, thereby inhibiting alloy-shell interfacial reactions, and improving surface quality of the alloys.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"51 23","pages":"Pages 40087-40097"},"PeriodicalIF":5.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922812","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}