Pub Date : 2024-10-15DOI: 10.1016/j.jeurceramsoc.2024.116992
Laura Silvestroni , Hai-Tao Liu , Diletta Sciti , Xin-Gang Wang , Guo-Jun Zhang
The effect of rare earth oxides (REO), Nd2O3 and Eu2O3, on the densification and oxidation behavior of pressureless sintered ZrB2-MoSi2 ceramic composites was investigated. Addition of REO results in the formation of REO-silicates which are liquid at the sintering temperature and contribute to matter transfer mechanisms. Oxidation studies at 1500 °C for 0.5–4 h evidenced that Eu2O3 can improve oxidation resistance in the ZrB2-MoSi2 system, especially after prolonged exposition, whilst Nd2O3 induces faster degradation of the ceramic. It was found that the Eu dispersed both in silica and in zirconia modifies the rheological properties of the glassy phase thus playing an important role in hindering oxygen inward from the atmosphere to the subsurface, resulting in a noticeable improvement of the oxidation resistance.
{"title":"Rare earth-doped ZrB2-MoSi2 ceramics: Densification and oxidation behavior","authors":"Laura Silvestroni , Hai-Tao Liu , Diletta Sciti , Xin-Gang Wang , Guo-Jun Zhang","doi":"10.1016/j.jeurceramsoc.2024.116992","DOIUrl":"10.1016/j.jeurceramsoc.2024.116992","url":null,"abstract":"<div><div>The effect of rare earth oxides (REO), Nd<sub>2</sub>O<sub>3</sub> and Eu<sub>2</sub>O<sub>3</sub>, on the densification and oxidation behavior of pressureless sintered ZrB<sub>2</sub>-MoSi<sub>2</sub> ceramic composites was investigated. Addition of REO results in the formation of REO-silicates which are liquid at the sintering temperature and contribute to matter transfer mechanisms. Oxidation studies at 1500 °C for 0.5–4 h evidenced that Eu<sub>2</sub>O<sub>3</sub> can improve oxidation resistance in the ZrB<sub>2</sub>-MoSi<sub>2</sub> system, especially after prolonged exposition, whilst Nd<sub>2</sub>O<sub>3</sub> induces faster degradation of the ceramic. It was found that the Eu dispersed both in silica and in zirconia modifies the rheological properties of the glassy phase thus playing an important role in hindering oxygen inward from the atmosphere to the subsurface, resulting in a noticeable improvement of the oxidation resistance.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116992"},"PeriodicalIF":5.8,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527706","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}
Pub Date : 2024-10-15DOI: 10.1016/j.jeurceramsoc.2024.116987
Guo Feng , Tiantian Liu , Feng Jiang , Zhiqi Guo , Liangliang Xiao , Qian Wu , Xiaojun Zhang , Qing Hu , Jianmin Liu , Jian Liang
Novel Co and Cr free, high-temperature (Ni, Mn) co-doping (CuFe)Fe4O8 black ceramic pigment was synthesized. The results indicate that the brightness (L*) values of the synthesized pigments decrease first, then reach an optimal value, and then increase with the doping amounts increasing of both Ni2O3 and MnO2. The optimized Ni2O3 and MnO2 doping amounts are 0.20 (molar ratio to (CuFe)Fe4O8) and 0.75 (molar ratio to (CuFe)Fe4O8), respectively. L*, a* and b* values of the optimized pigment (0.20Ni, 0.75Mn) co-doping (CuFe)Fe4O8 are 21.36, 1.10 and −0.24, respectively. The crystal phase of the optimized pigment is (CuFe)Fe4O8 (JCPDS73–2314). The crystal size of the pigment is 0.8–1.5μm with excellent dispersivity. The glazing temperatures have little effect on the coloration of the pigment when used at 1000℃, 1150℃ and 1300℃. The results show that the pigments have excellent high-temperature resistance and are expected to be widely used in high-temperature glazing coloration.
{"title":"Novel Co and Cr free, high-temperature black ceramic pigment based on (Ni, Mn) co-doping (CuFe)Fe4O8","authors":"Guo Feng , Tiantian Liu , Feng Jiang , Zhiqi Guo , Liangliang Xiao , Qian Wu , Xiaojun Zhang , Qing Hu , Jianmin Liu , Jian Liang","doi":"10.1016/j.jeurceramsoc.2024.116987","DOIUrl":"10.1016/j.jeurceramsoc.2024.116987","url":null,"abstract":"<div><div>Novel Co and Cr free, high-temperature (Ni, Mn) co-doping (CuFe)Fe<sub>4</sub>O<sub>8</sub> black ceramic pigment was synthesized. The results indicate that the brightness (L*) values of the synthesized pigments decrease first, then reach an optimal value, and then increase with the doping amounts increasing of both Ni<sub>2</sub>O<sub>3</sub> and MnO<sub>2</sub>. The optimized Ni<sub>2</sub>O<sub>3</sub> and MnO<sub>2</sub> doping amounts are 0.20 (molar ratio to (CuFe)Fe<sub>4</sub>O<sub>8</sub>) and 0.75 (molar ratio to (CuFe)Fe<sub>4</sub>O<sub>8</sub>), respectively. L*, a* and b* values of the optimized pigment (0.20Ni, 0.75Mn) co-doping (CuFe)Fe<sub>4</sub>O<sub>8</sub> are 21.36, 1.10 and −0.24, respectively. The crystal phase of the optimized pigment is (CuFe)Fe<sub>4</sub>O<sub>8</sub> (JCPDS73–2314). The crystal size of the pigment is 0.8–1.5<em>μ</em>m with excellent dispersivity. The glazing temperatures have little effect on the coloration of the pigment when used at 1000℃, 1150℃ and 1300℃. The results show that the pigments have excellent high-temperature resistance and are expected to be widely used in high-temperature glazing coloration.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116987"},"PeriodicalIF":5.8,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142438098","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}
Pub Date : 2024-10-15DOI: 10.1016/j.jeurceramsoc.2024.116985
A. Bident, J. Roger, A. Ebel, F. Rebillat
SiC-based materials are good candidates for structural applications at high temperature. However, due to their limited damage tolerance, in-service health monitoring using electrical conductivity measurements would be beneficial. Still, electrical measurements in hot zones on these materials remain a major challenge and require the design of a specific contact material that ensure adhesion of the measurement wires to the material while limiting chemical reactivity with the substrate. TiSi2-Si eutectic compound was found to be a good candidate for this application. An electrical conductivity (EC) measurement was carried out up successfully to 1300 °C in vacuum on a sintered SiC sample using this contact material. Post-measurement analysis of the contact was carried out, and cracks and SiC growth were observed, but without any impact on the electrical resistance measurement.
{"title":"Hot zone electrical resistance measurement for health monitoring of SiC and Si-based materials","authors":"A. Bident, J. Roger, A. Ebel, F. Rebillat","doi":"10.1016/j.jeurceramsoc.2024.116985","DOIUrl":"10.1016/j.jeurceramsoc.2024.116985","url":null,"abstract":"<div><div>SiC-based materials are good candidates for structural applications at high t<del>e</del>mperature. However, due to their limited damage tolerance, in-service health monitoring using electrical conductivity measurements would be beneficial. Still, electrical measurements in hot zones on these materials remain a major challenge and require the design of a specific contact material that ensure adhesion of the measurement wires to the material while limiting chemical reactivity with the substrate. TiSi<sub>2</sub>-Si eutectic compound was found to be a good candidate for this application. An electrical conductivity (EC) measurement was carried out up successfully to 1300 °C in vacuum on a sintered SiC sample using this contact material. Post-measurement analysis of the contact was carried out, and cracks and SiC growth were observed, but without any impact on the electrical resistance measurement.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116985"},"PeriodicalIF":5.8,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527704","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}
Pub Date : 2024-10-15DOI: 10.1016/j.jeurceramsoc.2024.116988
Zhongmin Li , Xun Zhang , Han Liu , Philip J. Withers , Ping Xiao
The present study investigates the microstructure evolution and subsequent mechanical properties of SiCfiber/BN/SiBCNmatrix composites after high temperature exposure. These composites display a tough failure response under three-point bending retaining 80 % of the as-processed strength, even after elevated temperature exposure up to 1350 °C for 10 h. This is due to crack deflection accompanied by extensive fiber pull-out. In addition, both thermodynamic modelling and phase analysis by XRD show higher matrix degradation in vacuum than in N2 atmosphere due to the lower N2 partial pressure. After thermally exposure at 1500°C, carbothermal reaction in the matrix leads to the formation of a porous composite, and the composites retains a tough failure response. Meanwhile, SiBCN matrix degradation and SiC fiber strength degradation occurs, which results in a significant decrement in composite strength. Modest increases in the fiber/matrix interfacial shear strength occur upon exposure at temperatures up to 1350°C, and then significantly reduce upon exposure to 1500 °C in N2.
{"title":"Microstructure evolution and mechanical properties of SiCf/BN/SiBCN composite after high temperature thermal exposure","authors":"Zhongmin Li , Xun Zhang , Han Liu , Philip J. Withers , Ping Xiao","doi":"10.1016/j.jeurceramsoc.2024.116988","DOIUrl":"10.1016/j.jeurceramsoc.2024.116988","url":null,"abstract":"<div><div>The present study investigates the microstructure evolution and subsequent mechanical properties of SiC<sub>fiber</sub>/BN/SiBCN<sub>matrix</sub> composites after high temperature exposure. These composites display a tough failure response under three-point bending retaining 80 % of the as-processed strength, even after elevated temperature exposure up to 1350 °C for 10 h. This is due to crack deflection accompanied by extensive fiber pull-out. In addition, both thermodynamic modelling and phase analysis by XRD show higher matrix degradation in vacuum than in N<sub>2</sub> atmosphere due to the lower N<sub>2</sub> partial pressure. After thermally exposure at 1500°C, carbothermal reaction in the matrix leads to the formation of a porous composite, and the composites retains a tough failure response. Meanwhile, SiBCN matrix degradation and SiC fiber strength degradation occurs, which results in a significant decrement in composite strength. Modest increases in the fiber/matrix interfacial shear strength occur upon exposure at temperatures up to 1350°C, and then significantly reduce upon exposure to 1500 °C in N<sub>2</sub>.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116988"},"PeriodicalIF":5.8,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142561490","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}
Pub Date : 2024-10-12DOI: 10.1016/j.jeurceramsoc.2024.116986
Ruihang Li , Luchao Ren , Le Xin , Pengchao Shao , Jia Wang , Zengli Gao , Panpan Lyu , Cuncheng Li , Hui Peng , Mingwei Zhang
This study optimizes the temperature coefficient of resonant frequency (τf) in CuMoO4 ceramics from −36 to −8.82 ppm/°C through W6+ B-site substitution. XRD analysis confirms the single-phase structure of CuMo1-xWxO4 ceramics, while Rietveld refinements reveal an expansion in lattice parameters. W6+ substitution slightly reduces the relative permittivity (εr) due to the changes in sintering density and ion polarizability. Moreover, the internal effects of W6+ substitution on the Q×f value are systematically investigated by analyzing the Raman peak's full width at half maximum (FWHM) and conducting packing fraction calculations. Additionally, lattice distortion and bond valence analyses elucidate the intrinsic mechanism behind τf improvement. Consequently, when x = 0.08, CuMo1-xWxO4 sintered at 625°C exhibits superior overall performance: εr = 5.13, Q×f = 65,506 GHz, τf = −8.82 ppm/°C. Furthermore, it demonstrates good chemical compatibility with Al electrodes making the material more suitable for ULTCC practical applications.
{"title":"W6+ doped CuMoO4 ceramics with low dielectric permittivity and near-zero temperature coefficient of resonant frequency for ULTCC application","authors":"Ruihang Li , Luchao Ren , Le Xin , Pengchao Shao , Jia Wang , Zengli Gao , Panpan Lyu , Cuncheng Li , Hui Peng , Mingwei Zhang","doi":"10.1016/j.jeurceramsoc.2024.116986","DOIUrl":"10.1016/j.jeurceramsoc.2024.116986","url":null,"abstract":"<div><div>This study optimizes the temperature coefficient of resonant frequency (τ<sub>f</sub>) in CuMoO<sub>4</sub> ceramics from −36 to −8.82 ppm/°C through W<sup>6+</sup> B-site substitution. XRD analysis confirms the single-phase structure of CuMo<sub>1-<em>x</em></sub>W<sub><em>x</em></sub>O<sub>4</sub> ceramics, while Rietveld refinements reveal an expansion in lattice parameters. W<sup>6+</sup> substitution slightly reduces the relative permittivity (ε<sub>r</sub>) due to the changes in sintering density and ion polarizability. Moreover, the internal effects of W<sup>6+</sup> substitution on the Q×f value are systematically investigated by analyzing the Raman peak's full width at half maximum (FWHM) and conducting packing fraction calculations. Additionally, lattice distortion and bond valence analyses elucidate the intrinsic mechanism behind τ<sub>f</sub> improvement. Consequently, when <em>x</em> = 0.08, CuMo<sub>1-<em>x</em></sub>W<sub><em>x</em></sub>O<sub>4</sub> sintered at 625°C exhibits superior overall performance: ε<sub>r</sub> = 5.13, Q×f = 65,506 GHz, τ<sub>f</sub> = −8.82 ppm/°C. Furthermore, it demonstrates good chemical compatibility with Al electrodes making the material more suitable for ULTCC practical applications.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116986"},"PeriodicalIF":5.8,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434042","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}
Pub Date : 2024-10-11DOI: 10.1016/j.jeurceramsoc.2024.116982
Ning Han , Shoulei Yang , Shuyue Chen , Zhiyi Wang , Mengjie Yang , Lei Fan , Xiaoqing Guo , Yujin Dai , Yidan Wang , Shuangqing Chen , Zhengkai Zhang , Yun Zhang
This study investigates the effects of limiting current density and current step rate on the microstructure and hardness of current-step flash-sintered (CS-FS) disc-shaped MgAl2O4 ceramics. The results indicated that, unlike conventional flash sintering, the temperature of the sample during the current-step flash started at a lower initial value and subsequently increased gradually. Furthermore, the differences in oxygen vacancies between the positive and negative sides of the CS-FS-ed MgAl2O4 ceramics were significantly reduced. This led to the CS-FS samples exhibiting higher relative density, finer grain size, a more uniform microstructure, and increased hardness. The homogeneous microstructure resulted in consistent hardness across both sides of each CS-FS-ed sample. Additionally, as the limiting current density increased, the grain sizes near the positive and negative sides gradually enlarged, while the relative density initially increased before decreasing. A similar trend was observed when the current step rate decreased.
{"title":"Effects of limiting current density and current step rate on microstructure and hardness of flash sintered MgAl2O4 ceramics","authors":"Ning Han , Shoulei Yang , Shuyue Chen , Zhiyi Wang , Mengjie Yang , Lei Fan , Xiaoqing Guo , Yujin Dai , Yidan Wang , Shuangqing Chen , Zhengkai Zhang , Yun Zhang","doi":"10.1016/j.jeurceramsoc.2024.116982","DOIUrl":"10.1016/j.jeurceramsoc.2024.116982","url":null,"abstract":"<div><div>This study investigates the effects of limiting current density and current step rate on the microstructure and hardness of current-step flash-sintered (CS-FS) disc-shaped MgAl<sub>2</sub>O<sub>4</sub> ceramics. The results indicated that, unlike conventional flash sintering, the temperature of the sample during the current-step flash started at a lower initial value and subsequently increased gradually. Furthermore, the differences in oxygen vacancies between the positive and negative sides of the CS-FS-ed MgAl<sub>2</sub>O<sub>4</sub> ceramics were significantly reduced. This led to the CS-FS samples exhibiting higher relative density, finer grain size, a more uniform microstructure, and increased hardness. The homogeneous microstructure resulted in consistent hardness across both sides of each CS-FS-ed sample. Additionally, as the limiting current density increased, the grain sizes near the positive and negative sides gradually enlarged, while the relative density initially increased before decreasing. A similar trend was observed when the current step rate decreased.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116982"},"PeriodicalIF":5.8,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434044","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}
Pub Date : 2024-10-11DOI: 10.1016/j.jeurceramsoc.2024.116983
Chang Peng , Ming-Zhu Pan , Jia-Min Wu , Jin-Feng Yan , Qian-Xun Liu , Xiao-Yan Zhang , Xiu-Mei Wang , Yu-Sheng Shi
Bone defects resulting from bone tumor resections are often complicated with residual cancer cells. To address the challenge, the magnetothermal porous structured bone scaffolds of hydroxyapatite-Fe3O4-MgO (HA-FM) were fabricated by Vat Photopolymerization (VPP). This study improved curing behavior by doping Mg(OH)2 into Fe3O4 powder via the chemical deposition method. Mg(OH)2 functioned as a pore-forming agent during the sintering process, decomposing into MgO to enhance biocompatibility. A two-step debinding method combined with a carbon powder embedding sintering process was used employed to resolve the conflict between the removal of photosensitive resin and the oxidation of Fe3O4. After sintering at 1200°C, the porosity of the composite ceramics reached 69 % and a compressive strength of 2.28 MPa. In vitro mineralization tests showed that doping with Fe3O4 and Mg(OH)2 could promote the scaffolds’ degradation in simulated body fluid (SBF), beneficial to mineralization process. In vitro cell proliferation and adhesion experiments showed that ceramic samples were not cytotoxic and could promote osteogenic differentiation. The composite scaffolds exhibited magnetothermal properties, achieving a temperature increase of 8.2°C in the alternating magnetic field of 92 G and 100 kHz, indicating potential for cancer treatment.
{"title":"Preparation of magnetothermal Fe3O4/MgO/HA composite scaffolds for cancer hyperthermia by Vat Photopolymerization","authors":"Chang Peng , Ming-Zhu Pan , Jia-Min Wu , Jin-Feng Yan , Qian-Xun Liu , Xiao-Yan Zhang , Xiu-Mei Wang , Yu-Sheng Shi","doi":"10.1016/j.jeurceramsoc.2024.116983","DOIUrl":"10.1016/j.jeurceramsoc.2024.116983","url":null,"abstract":"<div><div>Bone defects resulting from bone tumor resections are often complicated with residual cancer cells. To address the challenge, the magnetothermal porous structured bone scaffolds of hydroxyapatite-Fe<sub>3</sub>O<sub>4</sub>-MgO (HA-FM) were fabricated by Vat Photopolymerization (VPP). This study improved curing behavior by doping Mg(OH)<sub>2</sub> into Fe<sub>3</sub>O<sub>4</sub> powder via the chemical deposition method. Mg(OH)<sub>2</sub> functioned as a pore-forming agent during the sintering process, decomposing into MgO to enhance biocompatibility. A two-step debinding method combined with a carbon powder embedding sintering process was used employed to resolve the conflict between the removal of photosensitive resin and the oxidation of Fe<sub>3</sub>O<sub>4</sub>. After sintering at 1200°C, the porosity of the composite ceramics reached 69 % and a compressive strength of 2.28 MPa. In vitro mineralization tests showed that doping with Fe<sub>3</sub>O<sub>4</sub> and Mg(OH)<sub>2</sub> could promote the scaffolds’ degradation in simulated body fluid (SBF), beneficial to mineralization process. In vitro cell proliferation and adhesion experiments showed that ceramic samples were not cytotoxic and could promote osteogenic differentiation. The composite scaffolds exhibited magnetothermal properties, achieving a temperature increase of 8.2°C in the alternating magnetic field of 92 G and 100 kHz, indicating potential for cancer treatment.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116983"},"PeriodicalIF":5.8,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527705","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}
Pub Date : 2024-10-11DOI: 10.1016/j.jeurceramsoc.2024.116984
Yuzhi Zhai , Xudong Qi , Gang Tian , Jianxu Wang , Fapeng Yu , Zhigang Gai , Juan Du , Wenbin Su , Shiyi Guo , Limei Zheng
Textured CuO-doped KNN-based ceramics with [001]C orientation were developed to enhance energy harvesting performance. Textured ceramics doped with 0.3 mol% CuO exhibit remarkable piezoelectric coefficients d33 of 347 pC/N and g33 of 96 × 10−3 Vm/N, resulting in a higher figure of merit (d33 × g33 ∼ 33 × 10−12 m2/N) for evaluating energy conversion. The d33 and g33 increased by 105 % and 269 %, respectively, compared to those of randomly oriented ceramics. The piezoelectric energy harvester fabricated using the textured ceramic achieved an output power density of 3 μW/mm3, comparable to PZT-based energy harvesters. The enhancement in d33 is mainly due to favorable [00 l]C orientation. The orientation, along with the hardening effect caused by CuO doping, contributes to decreased dielectric coefficient εTr3, resulting in increased g33. The synergistic strategy is expected to facilitate the design high-performing, eco-friendly piezoelectric ceramics.
{"title":"Improved energy-harvesting performance of (K, Na)NbO3-based ceramics through the synergistic effect of texture and defect engineering","authors":"Yuzhi Zhai , Xudong Qi , Gang Tian , Jianxu Wang , Fapeng Yu , Zhigang Gai , Juan Du , Wenbin Su , Shiyi Guo , Limei Zheng","doi":"10.1016/j.jeurceramsoc.2024.116984","DOIUrl":"10.1016/j.jeurceramsoc.2024.116984","url":null,"abstract":"<div><div>Textured CuO-doped KNN-based ceramics with [001]<sub>C</sub> orientation were developed to enhance energy harvesting performance. Textured ceramics doped with 0.3 mol% CuO exhibit remarkable piezoelectric coefficients <em>d</em><sub>33</sub> of 347 pC/N and <em>g</em><sub>33</sub> of 96 × 10<sup>−3</sup> Vm/N, resulting in a higher figure of merit (<em>d</em><sub>33</sub> × <em>g</em><sub>33</sub> ∼ 33 × 10<sup>−12</sup> m<sup>2</sup>/N) for evaluating energy conversion. The <em>d</em><sub>33</sub> and <em>g</em><sub>33</sub> increased by 105 % and 269 %, respectively, compared to those of randomly oriented ceramics. The piezoelectric energy harvester fabricated using the textured ceramic achieved an output power density of 3 μW/mm<sup>3</sup>, comparable to PZT-based energy harvesters. The enhancement in <em>d</em><sub>33</sub> is mainly due to favorable [00 l]<sub>C</sub> orientation. The orientation, along with the hardening effect caused by CuO doping, contributes to decreased dielectric coefficient <em>ε</em><sup>T</sup><sub>r3</sub>, resulting in increased <em>g</em><sub>33</sub>. The synergistic strategy is expected to facilitate the design high-performing, eco-friendly piezoelectric ceramics.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116984"},"PeriodicalIF":5.8,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434045","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}
Pub Date : 2024-10-09DOI: 10.1016/j.jeurceramsoc.2024.116974
Yuan-Bin Chen, Siyi Xiong
This article explores the microwave dielectric properties of (La1-xNdx)2(Zr0.96Ti0.04)3(MoO4)9 (x=0.1,0.3,0.5, and 0.7) ceramics prepared by solid-state reaction. Utilizing the Rietveld refinement technique in XRD, the sample is identified as a trigonal crystal system belonging to the space group. SEM analysis indicates that relative density has a significant impact on the εr and Q×f of ceramics. The Q×f values of ceramics are closely related to the FWHM of the Raman spectra. At 750℃, (La0.5Nd0.5)2(Zr0.96Ti0.04)3(MoO4)9 ceramic exhibited excellent dielectric properties: εr = 10.4 (±0.08), Q×f = 149,300 (±3211) GHz, τf = −34.8 (±0.7) ppm/℃. To gain a deeper understanding of the intrinsic mechanisms governing the microwave dielectric properties of ceramics, analysis based on the P-V-L theory reveals that the La(Nd)-O bond and Mo-O bond contribute significantly to εr and Q×f, respectively.
{"title":"Structural characteristics, P-V-L theory, Raman spectra, and microwave dielectric properties of (La1-xNdx)2(Zr0.96Ti0.04)3(MoO4)9 ceramics for LTCC applications","authors":"Yuan-Bin Chen, Siyi Xiong","doi":"10.1016/j.jeurceramsoc.2024.116974","DOIUrl":"10.1016/j.jeurceramsoc.2024.116974","url":null,"abstract":"<div><div>This article explores the microwave dielectric properties of (La<sub>1-x</sub>Nd<sub>x</sub>)<sub>2</sub>(Zr<sub>0.96</sub>Ti<sub>0.04</sub>)<sub>3</sub>(MoO<sub>4</sub>)<sub>9</sub> (x=0.1,0.3,0.5, and 0.7) ceramics prepared by solid-state reaction. Utilizing the Rietveld refinement technique in XRD, the sample is identified as a trigonal crystal system belonging to the <span><math><mrow><mi>R</mi><mover><mrow><mn>3</mn></mrow><mo>¯</mo></mover><mi>c</mi></mrow></math></span> space group. SEM analysis indicates that relative density has a significant impact on the ε<sub>r</sub> and Q×f of ceramics. The Q×f values of ceramics are closely related to the FWHM of the Raman spectra. At 750℃, (La<sub>0.5</sub>Nd<sub>0.5</sub>)<sub>2</sub>(Zr<sub>0.96</sub>Ti<sub>0.04</sub>)<sub>3</sub>(MoO<sub>4</sub>)<sub>9</sub> ceramic exhibited excellent dielectric properties: ε<sub>r</sub> = 10.4 (±0.08), Q×f = 149,300 (±3211) GHz, τ<sub>f</sub> = −34.8 (±0.7) ppm/℃. To gain a deeper understanding of the intrinsic mechanisms governing the microwave dielectric properties of ceramics, analysis based on the P-V-L theory reveals that the La(Nd)-O bond and Mo-O bond contribute significantly to ε<sub>r</sub> and Q×f, respectively.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116974"},"PeriodicalIF":5.8,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434043","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}
In this work, the influence of refractory Zr and Ti and their combination (Zr,Ti) on the oxidation behavior of the (Hf,Ta,Nb)(C,N) carbonitride under non-isothermal and isothermal conditions at 1200 °C was studied, the effect of nitrogen addition was demonstrated, and a possible oxidation mechanisms were identified. The best result was achieved for high-entropy carbonitride (Hf,Ta,Nb,Zr,Ti)(C,N). The introduction of nitrogen into the of high-entropy carbide lattice contributed to a decrease in the specific weight gain by 12 %, and the addition of Ti, Zr, and (Zr,Ti) to the (Hf,Ta,Nb)(C,N) – a decrease of 47, 65, and 83 %, respectively.
{"title":"High-entropy carbonitrides with superior oxidation resistance: Fabrication and investigation of oxidation behavior under non-isothermal and isothermal conditions","authors":"Veronika Suvorova , Dmitrii Suvorov , Sergey Volodko , Maksim Poliakov , Lidiya Volkova , Andrey Nepapushev , Dmitry Moskovskikh","doi":"10.1016/j.jeurceramsoc.2024.116980","DOIUrl":"10.1016/j.jeurceramsoc.2024.116980","url":null,"abstract":"<div><div>In this work, the influence of refractory Zr and Ti and their combination (Zr,Ti) on the oxidation behavior of the (Hf,Ta,Nb)(C,N) carbonitride under non-isothermal and isothermal conditions at 1200 °C was studied, the effect of nitrogen addition was demonstrated, and a possible oxidation mechanisms were identified. The best result was achieved for high-entropy carbonitride (Hf,Ta,Nb,Zr,Ti)(C,N). The introduction of nitrogen into the of high-entropy carbide lattice contributed to a decrease in the specific weight gain by 12 %, and the addition of Ti, Zr, and (Zr,Ti) to the (Hf,Ta,Nb)(C,N) – a decrease of 47, 65, and 83 %, respectively.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"45 3","pages":"Article 116980"},"PeriodicalIF":5.8,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142420874","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}
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