High-performance dielectric energy-storage ceramics are indispensable core components in pulsed power systems. Despite progress in enhancing energy storage performance, there are still significant constraints among various macroscopic performance parameters, hindering their miniaturization and integration into devices. Herein, we propose a novel weakly coupled relaxor ferroelectric ceramic system that delays premature polarization saturation of BaTiO3-based ceramics to achieve the desirable energy storage characteristics. The ceramic exhibits a high energy storage density (Wrec) of ∼4.58 J cm−3 and high energy efficiency (η) of ∼95.2 % under an electric field of 540 kV cm−1, along with good performance stability in the range of 40–160 °C and 1–120 Hz. Furthermore, the enhanced insulation properties and refined average grain size contribute to the high breakdown field strength (Eb) of the system. These findings provide a viable framework for the design of dielectric ceramic capacitors with high energy-storage characteristics.
{"title":"Synergistic optimization of delayed polarization saturation and enhanced breakdown strength in lead-free capacitors for superior energy storage characteristics","authors":"Hailin Zhang, Peng Nong, Haochen Duan, Youya Ke, Xiuli Chen, Xu Li, Huanfu Zhou","doi":"10.1016/j.ceramint.2024.09.156","DOIUrl":"10.1016/j.ceramint.2024.09.156","url":null,"abstract":"<div><div>High-performance dielectric energy-storage ceramics are indispensable core components in pulsed power systems. Despite progress in enhancing energy storage performance, there are still significant constraints among various macroscopic performance parameters, hindering their miniaturization and integration into devices. Herein, we propose a novel weakly coupled relaxor ferroelectric ceramic system that delays premature polarization saturation of BaTiO<sub>3</sub>-based ceramics to achieve the desirable energy storage characteristics. The ceramic exhibits a high energy storage density (<em>W</em><sub>rec</sub>) of ∼4.58 J cm<sup>−3</sup> and high energy efficiency (<em>η</em>) of ∼95.2 % under an electric field of 540 kV cm<sup>−1</sup>, along with good performance stability in the range of 40–160 °C and 1–120 Hz. Furthermore, the enhanced insulation properties and refined average grain size contribute to the high breakdown field strength (<em>E</em><sub>b</sub>) of the system. These findings provide a viable framework for the design of dielectric ceramic capacitors with high energy-storage characteristics.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"50 22","pages":"Pages 48084-48091"},"PeriodicalIF":5.1,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262605","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}
<p>High-entropy boride ceramics are expected to be widely used in aerospace, automotive turbines, and armor protection due to their advantages of high melting point, high hardness, adjustable performance, high-temperature stability, and good oxidation resistance. However, it is urgent to solve the problem of low fracture toughness before application. Therefore, in this paper, a single-phase high-purity (Ti<sub>0.2</sub>Zr<sub>0.2</sub>Hf<sub>0.2</sub>Nb<sub>0.2</sub>Ta<sub>0.2</sub>)B<sub>2</sub> powder was prepared by boron/carbon thermal reduction method using a vacuum furnace. The effects of synthesis temperature and C content on the powder were studied. Secondly, HEB ((Ti<sub>0.2</sub>Zr<sub>0.2</sub>Hf<sub>0.2</sub>Nb<sub>0.2</sub>Ta<sub>0.2</sub>)B<sub>2</sub>) powder, SiC powder, and chopped Ta fiber were mixed uniformly, and Ta fiber toughened HEB-SiC composite ceramics were prepared by spark plasma sintering (SPS). The effects of Ta fiber content on the phase composition, microstructure, mechanical properties, and oxidation resistance of the composite ceramics were investigated. The results show that with the increase in synthesis temperature, the HEB powder gradually dissolves, and the solid solution is completely formed at 1700°C. As the C content increases, the oxygen content and particle size of the powder gradually decrease. Single-phase high-entropy (Ti<sub>0.2</sub>Zr<sub>0.2</sub>Hf<sub>0.2</sub>Nb<sub>0.2</sub>Ta<sub>0.2</sub>)B<sub>2</sub> powders with high purity were prepared at 1700°C for 1 h with 6 wt% C content. The addition of C will promote the boron/carbon thermal reduction method, reduce the oxygen content, and inhibit grain growth. With the increase of Ta fiber content, the density of HEB-SiC-Ta<sub>f</sub> composite ceramics increased first and then decreased. The hardness gradually decreased, and the fracture toughness gradually increased. When the Ta fiber content was 7 vol%, the fracture toughness was the highest, reaching 5.12 ± 0.39 MPa·m<sup>1/2</sup>, which was nearly 45% higher than that of the composite ceramics without Ta fiber. This is because of the synergistic toughening mechanism of metal toughening and fiber toughening, such as crack deflection, crack bridging, fiber debonding, and fiber pullout, which improves the fracture toughness of the composite ceramics. With the increase in oxidation temperature, B<sub>2</sub>O<sub>3</sub>, SiO<sub>2</sub>, Ta<sub>2</sub>O<sub>5</sub>, and various metal oxides appear on the surface of HEB-SiC-Ta<sub>f</sub> composite ceramics. The oxidation depth and weight gain per unit area gradually increase. When the Ta fiber content is 5 vol%, the composite ceramics exhibit the best high temperature stability and oxidation resistance. This is due to the Ta<sub>2</sub>O<sub>5</sub> formed by the oxidation of Ta fibers, which dissolves into the B<sub>2</sub>O<sub>3</sub> glass phase, increasing viscosity and improving high temperature stability while reducing the oxygen diffu
高熵硼化物陶瓷具有高熔点、高硬度、性能可调、高温稳定性和良好的抗氧化性等优点，有望广泛应用于航空航天、汽车涡轮机和装甲防护等领域。然而，在应用之前，迫切需要解决断裂韧性低的问题。因此，本文利用真空炉，采用硼/碳热还原法制备了单相高纯（Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2）B2 粉末。研究了合成温度和碳含量对粉末的影响。其次，将 HEB（(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)B2）粉末、SiC 粉末和切碎的 Ta 纤维混合均匀，采用火花等离子烧结法（SPS）制备了 Ta 纤维增韧 HEB-SiC 复合陶瓷。研究了 Ta 纤维含量对复合陶瓷的相组成、微观结构、力学性能和抗氧化性的影响。结果表明，随着合成温度的升高，HEB 粉末逐渐溶解，在 1700°C 时完全形成固溶体。随着 C 含量的增加，粉末的氧含量和粒度逐渐减小。在 1700℃、1 小时、C 含量为 6 wt% 的条件下，制备出了高纯度的单相高熵 (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)B2 粉末。C 的加入会促进硼/碳热还原法，降低氧含量，抑制晶粒长大。随着 Ta 纤维含量的增加，HEB-SiC-Taf 复合陶瓷的密度先增大后减小。硬度逐渐降低，断裂韧性逐渐增加。当 Ta 纤维含量为 7 vol% 时，断裂韧性最高，达到 5.12 ± 0.39 MPa-m1/2，比不添加 Ta 纤维的复合陶瓷高出近 45%。这是因为金属增韧和纤维增韧的协同增韧机理，如裂纹偏转、裂纹架桥、纤维脱粘和纤维拔出等，提高了复合陶瓷的断裂韧性。随着氧化温度的升高，HEB-SiC-Taf 复合陶瓷表面会出现 B2O3、SiO2、Ta2O5 和各种金属氧化物。氧化深度和单位面积增重逐渐增加。当 Ta 纤维含量为 5 vol% 时，复合陶瓷表现出最佳的高温稳定性和抗氧化性。这是由于 Ta 纤维氧化形成的 Ta2O5 溶解到 B2O3 玻璃相中，增加了粘度，提高了高温稳定性，同时降低了氧扩散率。
{"title":"Preparation and Properties of Ta Fiber Reinforced High-entropy (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)B2-SiC Composite Ceramics","authors":"Qilong Guo, Hao Ying, Bowen Yuan, Hengzhong Fan, Liang Hua, Ronghao Liu, Jing Wang","doi":"10.1016/j.ceramint.2024.09.266","DOIUrl":"https://doi.org/10.1016/j.ceramint.2024.09.266","url":null,"abstract":"<p>High-entropy boride ceramics are expected to be widely used in aerospace, automotive turbines, and armor protection due to their advantages of high melting point, high hardness, adjustable performance, high-temperature stability, and good oxidation resistance. However, it is urgent to solve the problem of low fracture toughness before application. Therefore, in this paper, a single-phase high-purity (Ti<sub>0.2</sub>Zr<sub>0.2</sub>Hf<sub>0.2</sub>Nb<sub>0.2</sub>Ta<sub>0.2</sub>)B<sub>2</sub> powder was prepared by boron/carbon thermal reduction method using a vacuum furnace. The effects of synthesis temperature and C content on the powder were studied. Secondly, HEB ((Ti<sub>0.2</sub>Zr<sub>0.2</sub>Hf<sub>0.2</sub>Nb<sub>0.2</sub>Ta<sub>0.2</sub>)B<sub>2</sub>) powder, SiC powder, and chopped Ta fiber were mixed uniformly, and Ta fiber toughened HEB-SiC composite ceramics were prepared by spark plasma sintering (SPS). The effects of Ta fiber content on the phase composition, microstructure, mechanical properties, and oxidation resistance of the composite ceramics were investigated. The results show that with the increase in synthesis temperature, the HEB powder gradually dissolves, and the solid solution is completely formed at 1700°C. As the C content increases, the oxygen content and particle size of the powder gradually decrease. Single-phase high-entropy (Ti<sub>0.2</sub>Zr<sub>0.2</sub>Hf<sub>0.2</sub>Nb<sub>0.2</sub>Ta<sub>0.2</sub>)B<sub>2</sub> powders with high purity were prepared at 1700°C for 1 h with 6 wt% C content. The addition of C will promote the boron/carbon thermal reduction method, reduce the oxygen content, and inhibit grain growth. With the increase of Ta fiber content, the density of HEB-SiC-Ta<sub>f</sub> composite ceramics increased first and then decreased. The hardness gradually decreased, and the fracture toughness gradually increased. When the Ta fiber content was 7 vol%, the fracture toughness was the highest, reaching 5.12 ± 0.39 MPa·m<sup>1/2</sup>, which was nearly 45% higher than that of the composite ceramics without Ta fiber. This is because of the synergistic toughening mechanism of metal toughening and fiber toughening, such as crack deflection, crack bridging, fiber debonding, and fiber pullout, which improves the fracture toughness of the composite ceramics. With the increase in oxidation temperature, B<sub>2</sub>O<sub>3</sub>, SiO<sub>2</sub>, Ta<sub>2</sub>O<sub>5</sub>, and various metal oxides appear on the surface of HEB-SiC-Ta<sub>f</sub> composite ceramics. The oxidation depth and weight gain per unit area gradually increase. When the Ta fiber content is 5 vol%, the composite ceramics exhibit the best high temperature stability and oxidation resistance. This is due to the Ta<sub>2</sub>O<sub>5</sub> formed by the oxidation of Ta fibers, which dissolves into the B<sub>2</sub>O<sub>3</sub> glass phase, increasing viscosity and improving high temperature stability while reducing the oxygen diffu","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"11 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262610","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}
This paper aims to enhance the surface quality of digital light processing (DLP) printed lead zirconate titanate (PZT) components by controlling the content of BYK-111 dispersant, thereby improving the electrical properties of the resulting printed piezoelectric ceramics and devices. 55 vol% high solid loading PZT slurries with different dispersant contents were prepared and assessed for their dispersion stability, rheological behavior and curing characteristics. The slurry containing 1 wt% BYK-111 demonstrated ideal rheological properties, notably achieving a low viscosity of 1.37 Pa·s at 100 s−1. The surface roughness of the printed ceramic component was reduced to 69.3 nm, representing a 57.1 % improvement in surface quality compared to other dispersant levels. The printed PZT ceramic exhibited superior piezoelectric performance, with a piezoelectric constant d33 reaching 445 pC/N, surpassing most existing 3D-printed macro-sized piezoelectric ceramics. Furthermore, a DLP-printed 1–3 piezoelectric array was encapsulated to fabricate an acoustic emission (AE) sensor, which achieved a low substrate noise level of 31 dB and a high signal-to-noise ratio of 62 dB, outperforming commercial sensors. The optimal BYK-111 content not only ensures favorable dispersion stability and rheological properties in the slurry, but also significantly enhances the surface quality and density of the printed ceramic components, ultimately leading to the production of high-performance piezoelectric ceramics and devices.
{"title":"Adjusting the surface quality of printed components via controlling dispersant content to improve the electrical performance of DLP-printed PZT ceramics and devices","authors":"Yaoting Zhao, Xiujuan Lin, Ruihang Liu, Rui Guo, Xiaofang Zhang, Qi Li, Wenlong Li, Chungang Li, Changhong Yang, Shifeng Huang","doi":"10.1016/j.ceramint.2024.09.258","DOIUrl":"10.1016/j.ceramint.2024.09.258","url":null,"abstract":"<div><div>This paper aims to enhance the surface quality of digital light processing (DLP) printed lead zirconate titanate (PZT) components by controlling the content of BYK-111 dispersant, thereby improving the electrical properties of the resulting printed piezoelectric ceramics and devices. 55 vol% high solid loading PZT slurries with different dispersant contents were prepared and assessed for their dispersion stability, rheological behavior and curing characteristics. The slurry containing 1 wt% BYK-111 demonstrated ideal rheological properties, notably achieving a low viscosity of 1.37 Pa·s at 100 s<sup>−1</sup>. The surface roughness of the printed ceramic component was reduced to 69.3 nm, representing a 57.1 % improvement in surface quality compared to other dispersant levels. The printed PZT ceramic exhibited superior piezoelectric performance, with a piezoelectric constant <em>d<sub>33</sub></em> reaching 445 pC/N, surpassing most existing 3D-printed macro-sized piezoelectric ceramics. Furthermore, a DLP-printed 1–3 piezoelectric array was encapsulated to fabricate an acoustic emission (AE) sensor, which achieved a low substrate noise level of 31 dB and a high signal-to-noise ratio of 62 dB, outperforming commercial sensors. The optimal BYK-111 content not only ensures favorable dispersion stability and rheological properties in the slurry, but also significantly enhances the surface quality and density of the printed ceramic components, ultimately leading to the production of high-performance piezoelectric ceramics and devices.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"50 23","pages":"Pages 49165-49175"},"PeriodicalIF":5.1,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262603","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 : 2024-09-20DOI: 10.1016/j.ceramint.2024.09.264
Qian Wang , Ying Bai , Na Zhao , Linan Wang , Fan Zhang , Yanqiu Zhu , Di Lan , Rui Zhang , Hailong Wang , Bingbing Fan
Ta4C3Tx MXene, a novel two-dimensional material, shows significant application potential for electromagnetic wave (EMW) absorption because of its unique layered structure and high conductivity. In this study, hydrofluoric acid etching was used to obtain Ta4C3Tx MXenes with varying interlayer spaces by adjusting the etching duration, which enhanced the EMW absorption performance. The impact of interlayer spacing on the EMW absorption performance of Ta4C3Tx MXene was systematically evaluated for the first time. The results show that the sample etched with hydrofluoric acid for 48 h (S2-48 h) exhibited the best EMW absorption performance. For S2-48 h, the optimal reflection loss (RL) value was −33.53 dB at a frequency of 9.74 GHz and a thickness of 1.4 mm. In addition, the widest effective absorption bandwidth was 2.97 GHz (10.73–13.7 GHz), which was achieved at a frequency of 11.72 GHz and a thickness of 1.2 mm. This outstanding performance is mainly attributed to good impedance matching and multiple loss mechanisms induced by the etching process, including conduction loss, dipolar polarization, interfacial polarization, and multiple RLs. Furthermore, this research expands the application potential of two-dimensional MXene materials in EMW absorption.
{"title":"Enhanced electromagnetic wave absorption performance of Ta₄C₃Tx MXenes with optimized interlayer spacing via hydrofluoric acid etching","authors":"Qian Wang , Ying Bai , Na Zhao , Linan Wang , Fan Zhang , Yanqiu Zhu , Di Lan , Rui Zhang , Hailong Wang , Bingbing Fan","doi":"10.1016/j.ceramint.2024.09.264","DOIUrl":"10.1016/j.ceramint.2024.09.264","url":null,"abstract":"<div><div>Ta<sub>4</sub>C<sub>3</sub>T<em>x</em> MXene, a novel two-dimensional material, shows significant application potential for electromagnetic wave (EMW) absorption because of its unique layered structure and high conductivity. In this study, hydrofluoric acid etching was used to obtain Ta<sub>4</sub>C<sub>3</sub>T<em>x</em> MXenes with varying interlayer spaces by adjusting the etching duration, which enhanced the EMW absorption performance. The impact of interlayer spacing on the EMW absorption performance of Ta<sub>4</sub>C<sub>3</sub>T<em>x</em> MXene was systematically evaluated for the first time. The results show that the sample etched with hydrofluoric acid for 48 h (S2-48 h) exhibited the best EMW absorption performance. For S2-48 h, the optimal reflection loss (RL) value was −33.53 dB at a frequency of 9.74 GHz and a thickness of 1.4 mm. In addition, the widest effective absorption bandwidth was 2.97 GHz (10.73–13.7 GHz), which was achieved at a frequency of 11.72 GHz and a thickness of 1.2 mm. This outstanding performance is mainly attributed to good impedance matching and multiple loss mechanisms induced by the etching process, including conduction loss, dipolar polarization, interfacial polarization, and multiple RLs. Furthermore, this research expands the application potential of two-dimensional MXene materials in EMW absorption.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"50 23","pages":"Pages 49217-49225"},"PeriodicalIF":5.1,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262612","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 : 2024-09-20DOI: 10.1016/j.ceramint.2024.09.257
Qiong Xie, Maxime Cavillon, Matthieu Lancry
Volume nanogratings (NGs) imprinted by infrared femtosecond laser in commercial optical glasses take the form of orientable subwavelength birefringent nanostructures, being composed of an assembly of nanopores. The existence of NGs strongly depends on the laser parameters and glass composition. Therefore, in this work, we tentatively model the erasure threshold of NGs in a pulse energy - repetition rate processing window. For this purpose, we combine i) a heat diffusion model to simulate the thermal treatment experienced by the glass upon laser irradiation, and ii) the Rayleigh-Plesset equation to take into account the evolution of a nanopore size during laser processing. We first determine a criterion for nanopores erasure, falling within a typical characteristic time of few tens of ns, for which the cooling of the last laser pulse absorbed by the material is progressively cooled. Then, considering a multipulse regime, and the dependence of the deposited pulse number on the thermal treatment experienced by the glass, the modeled NGs erasure threshold follows the experimental trend. Finally, by using a steady state regime for various repetition rates and adjusting the energy deposition (absorption coefficient or beam waist) as a function of the pulse energy, the NGs existence window can perfectly match the experimental values.
{"title":"Modeling nanogratings erasure at high repetition rate in commercial optical glasses","authors":"Qiong Xie, Maxime Cavillon, Matthieu Lancry","doi":"10.1016/j.ceramint.2024.09.257","DOIUrl":"10.1016/j.ceramint.2024.09.257","url":null,"abstract":"<div><div>Volume nanogratings (NGs) imprinted by infrared femtosecond laser in commercial optical glasses take the form of orientable subwavelength birefringent nanostructures, being composed of an assembly of nanopores. The existence of NGs strongly depends on the laser parameters and glass composition. Therefore, in this work, we tentatively model the erasure threshold of NGs in a pulse energy - repetition rate processing window. For this purpose, we combine i) a heat diffusion model to simulate the thermal treatment experienced by the glass upon laser irradiation, and ii) the Rayleigh-Plesset equation to take into account the evolution of a nanopore size during laser processing. We first determine a criterion for nanopores erasure, falling within a typical characteristic time of few tens of ns, for which the cooling of the last laser pulse absorbed by the material is progressively cooled. Then, considering a multipulse regime, and the dependence of the deposited pulse number on the thermal treatment experienced by the glass, the modeled NGs erasure threshold follows the experimental trend. Finally, by using a steady state regime for various repetition rates and adjusting the energy deposition (absorption coefficient or beam waist) as a function of the pulse energy, the NGs existence window can perfectly match the experimental values.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"50 23","pages":"Pages 49157-49164"},"PeriodicalIF":5.1,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262601","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 : 2024-09-20DOI: 10.1016/j.ceramint.2024.09.263
Du Zhou , Chaozheng Ding , Weijie Han , Huibing Li , Haitao Zhang , Wentao Xu , Youfu Zhou
Highly sinterable nanopowder of 8 mol% yttria-stabilized cubic zirconia (8YSZ) was synthesized via a hydrothermal homogeneous precipitation (HHP) method. The nanopowder with an average particle size of 26 nm, exhibits good dispersibility, narrow particle size distribution and high purity, making it ideal raw material for preparing transparent ceramics. Utilizing spark plasma sintering (SPS) under mild conditions (1200–1350 °C, 80 MPa, 10 min) in contrast to hot isostatic pressing (HIP), cubic zirconia ceramics with favorable optical and mechanical properties were produced. The sample sintered at 1250 °C achieved the highest transmittance of 74 %@850 nm, significantly surpassing the performance of samples prepared from two other commercial 8YSZ powders. Furthermore, the specimen sintered at 1200 °C with a dense fine microstructure (relative density: 99.51 %, grain size: 460 nm), demonstrated the highest hardness and fracture toughness, reaching 15.72 GPa and 1.28 MPa m1/2, respectively.
{"title":"Low-temperature fabrication of zirconia transparent ceramics via hydrothermal nanopowder","authors":"Du Zhou , Chaozheng Ding , Weijie Han , Huibing Li , Haitao Zhang , Wentao Xu , Youfu Zhou","doi":"10.1016/j.ceramint.2024.09.263","DOIUrl":"10.1016/j.ceramint.2024.09.263","url":null,"abstract":"<div><div>Highly sinterable nanopowder of 8 mol% yttria-stabilized cubic zirconia (8YSZ) was synthesized via a hydrothermal homogeneous precipitation (HHP) method. The nanopowder with an average particle size of 26 nm, exhibits good dispersibility, narrow particle size distribution and high purity, making it ideal raw material for preparing transparent ceramics. Utilizing spark plasma sintering (SPS) under mild conditions (1200–1350 °C, 80 MPa, 10 min) in contrast to hot isostatic pressing (HIP), cubic zirconia ceramics with favorable optical and mechanical properties were produced. The sample sintered at 1250 °C achieved the highest transmittance of 74 %@850 nm, significantly surpassing the performance of samples prepared from two other commercial 8YSZ powders. Furthermore, the specimen sintered at 1200 °C with a dense fine microstructure (relative density: 99.51 %, grain size: 460 nm), demonstrated the highest hardness and fracture toughness, reaching 15.72 GPa and 1.28 MPa m<sup>1/2</sup>, respectively.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"50 23","pages":"Pages 49210-49216"},"PeriodicalIF":5.1,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262606","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 : 2024-09-19DOI: 10.1016/j.ceramint.2024.09.265
Yang Liu, Haiqing Deng, Xiuli Chen, Xu Li, Huanfu Zhou
By adopting the solid-state reaction method, rare-earth-based NaSrRE (WO4)3 (RE = Ce, Nd, Sm) ceramics were successfully synthesized. The investigation also focused on the relationship between the microstructure and microwave dielectric properties. X-ray diffraction (XRD) results indicated that NaSrRE (WO4)3 ceramics exhibit a tetragonal scheelite structure with a space group of I41/a. It was found that the incorporation of smaller rare earth ions leads to a reduction in cell volume. The NaSrCe(WO4)3 ceramics sintered at 1250 °C exhibited excellent dielectric properties with εr = 8.84, Q×f = 73128 GHz, τf = −47.17 ppm/°C, the NaSrNd(WO4)3 ceramics sintered at 1225 °C showed dielectric properties of εr = 9.14, Q×f = 47824 GHz, τf = −55.56 ppm/°C, and the NaSrSm(WO4)3 ceramics sintered at 1225 °C demonstrated excellent dielectric properties with εr = 9.31, Q×f = 69141 GHz, τf = −46.99 ppm/°C. In general, the incorporation of rare earth ions of varying sizes at the A site of the scheelite structure can enhance the dielectric properties of the ceramics to some extent.
{"title":"Relationship between the micro-structure and dielectric properties of novel rare earth based NaSrRE(WO4)3(RE=Ce, Nd, Sm) microwave ceramics","authors":"Yang Liu, Haiqing Deng, Xiuli Chen, Xu Li, Huanfu Zhou","doi":"10.1016/j.ceramint.2024.09.265","DOIUrl":"10.1016/j.ceramint.2024.09.265","url":null,"abstract":"<div><div>By adopting the solid-state reaction method, rare-earth-based NaSrRE (WO<sub>4</sub>)<sub>3</sub> (RE = Ce, Nd, Sm) ceramics were successfully synthesized. The investigation also focused on the relationship between the microstructure and microwave dielectric properties. X-ray diffraction (XRD) results indicated that NaSrRE (WO<sub>4</sub>)<sub>3</sub> ceramics exhibit a tetragonal scheelite structure with a space group of <em>I</em>4<sub>1</sub>/<em>a</em>. It was found that the incorporation of smaller rare earth ions leads to a reduction in cell volume. The NaSrCe(WO<sub>4</sub>)<sub>3</sub> ceramics sintered at 1250 °C exhibited excellent dielectric properties with <em>ε</em><sub><em>r</em></sub> = 8.84, <em>Q×f</em> = 73128 GHz, <em>τ</em><sub><em>f</em></sub> = −47.17 ppm/°C, the NaSrNd(WO<sub>4</sub>)<sub>3</sub> ceramics sintered at 1225 °C showed dielectric properties of <em>ε</em><sub><em>r</em></sub> = 9.14, <em>Q×f</em> = 47824 GHz, <em>τ</em><sub><em>f</em></sub> = −55.56 ppm/°C, and the NaSrSm(WO<sub>4</sub>)<sub>3</sub> ceramics sintered at 1225 °C demonstrated excellent dielectric properties with <em>ε</em><sub><em>r</em></sub> = 9.31, <em>Q×f</em> = 69141 GHz, <em>τ</em><sub><em>f</em></sub> = −46.99 ppm/°C. In general, the incorporation of rare earth ions of varying sizes at the A site of the scheelite structure can enhance the dielectric properties of the ceramics to some extent.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"50 23","pages":"Pages 49226-49234"},"PeriodicalIF":5.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262607","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 : 2024-09-19DOI: 10.1016/j.ceramint.2024.09.244
Yi-ling Dai , Dong-xu Yao , Yong-feng Xia , Ming Zhu , Jun Zhao , Feng Wang , Yu-Ping Zeng
For biomaterials, the macropore structure directly impacts both its mechanical properties and various biological effects. The Direct Ink Writing (DIW) technique offers precise control over pore structure during the preparation of porous silicon nitride (Si3N4) ceramics, an undervalued yet excellent bioceramic material. In this study, a novel aqueous Si3N4 paste with a solid content of 44.59 vol% was proposed, notable for its remarkable shape retention. Through adjustments in printing parameters, a series of porous Si3N4 ceramics with varying macropore sizes are successfully fabricated, exhibiting relative densities ranging from 45.72 % to 82.99 % and flexural strengths from 79.8 ± 13.5 MPa to 492.6 ± 75.2 MPa. Three macropore shapes were further designed by adjusting the printing angle. Results indicated the strength of parallelogram pores is ∼32 % higher than squares and∼45 % higher than triangles, consistent with the predicted changes in relative density through calculation.
{"title":"Preparation of porous Si3N4 ceramics with varied macropore structures by direct ink writing","authors":"Yi-ling Dai , Dong-xu Yao , Yong-feng Xia , Ming Zhu , Jun Zhao , Feng Wang , Yu-Ping Zeng","doi":"10.1016/j.ceramint.2024.09.244","DOIUrl":"10.1016/j.ceramint.2024.09.244","url":null,"abstract":"<div><div>For biomaterials, the macropore structure directly impacts both its mechanical properties and various biological effects. The Direct Ink Writing (DIW) technique offers precise control over pore structure during the preparation of porous silicon nitride (Si<sub>3</sub>N<sub>4</sub>) ceramics, an undervalued yet excellent bioceramic material. In this study, a novel aqueous Si<sub>3</sub>N<sub>4</sub> paste with a solid content of 44.59 vol% was proposed, notable for its remarkable shape retention. Through adjustments in printing parameters, a series of porous Si<sub>3</sub>N<sub>4</sub> ceramics with varying macropore sizes are successfully fabricated, exhibiting relative densities ranging from 45.72 % to 82.99 % and flexural strengths from 79.8 ± 13.5 MPa to 492.6 ± 75.2 MPa. Three macropore shapes were further designed by adjusting the printing angle. Results indicated the strength of parallelogram pores is ∼32 % higher than squares and∼45 % higher than triangles, consistent with the predicted changes in relative density through calculation.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"50 23","pages":"Pages 49033-49040"},"PeriodicalIF":5.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262656","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 : 2024-09-19DOI: 10.1016/j.ceramint.2024.09.251
Roman D. Mukhachev, Semyon T. Baidak, Alexey V. Lukoyanov
The electronic structure of the GdNiSb compound under pressure has been investigated in the course of first-principles calculations accounting for spin-orbit coupling. At ambient conditions this compound is found to be a narrow gap semiconductor with an indirect band gap of 0.38 eV. Decreasing in the cell volume leads to a gradual redistribution of the density of states caused by band broadening and partial delocalization of the electronic states, in particular the 3d Ni states are strongly modified. The band gap is closed when the volume of the lattice decreases by 35% or more with a slight metallization at the Fermi energy with the appearance of the Fermi surfaces. For the smaller volumes, the metallic states with non-trivial topological features are calculated for GdNiSb.
在第一原理计算过程中，考虑到自旋轨道耦合，研究了钆镍锑化合物在压力下的电子结构。研究发现，在环境条件下，这种化合物是一种间接带隙为 0.38 eV 的窄间隙半导体。电池体积的减小会导致电子态的带宽扩大和部分失焦，从而导致态密度逐渐重新分布，尤其是 3d Ni 态发生了强烈变化。当晶格体积减少 35% 或更多时，带隙关闭，费米能处出现轻微的金属化，费米面也随之出现。对于较小体积的钆镍锑，我们计算出了具有非三维拓扑特征的金属态。
{"title":"Narrow gap semiconductor to metal transition in GdNiSb under pressure P-18","authors":"Roman D. Mukhachev, Semyon T. Baidak, Alexey V. Lukoyanov","doi":"10.1016/j.ceramint.2024.09.251","DOIUrl":"https://doi.org/10.1016/j.ceramint.2024.09.251","url":null,"abstract":"<p>The electronic structure of the GdNiSb compound under pressure has been investigated in the course of first-principles calculations accounting for spin-orbit coupling. At ambient conditions this compound is found to be a narrow gap semiconductor with an indirect band gap of 0.38 eV. Decreasing in the cell volume leads to a gradual redistribution of the density of states caused by band broadening and partial delocalization of the electronic states, in particular the 3d Ni states are strongly modified. The band gap is closed when the volume of the lattice decreases by 35% or more with a slight metallization at the Fermi energy with the appearance of the Fermi surfaces. For the smaller volumes, the metallic states with non-trivial topological features are calculated for GdNiSb.</p>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"18 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262611","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 : 2024-09-19DOI: 10.1016/j.ceramint.2024.09.170
Neha Sharma , Sushanta Mandal , Sourav Marik
Recent advancements in high entropy oxides (HEOs) have sparked significant interest as a promising frontier in materials research, revolutionizing the landscape of material design and properties. They exhibit outstanding stability, intriguing functional properties, and unparalleled design flexibility enabled by the inclusion of multiple cations in these materials. In this study, we successfully stabilized several new high entropy spinel oxides with compositions (Ni0.2(Mg/Mn)0.2Co0.2Cu0.2Zn0.2)BO (B = Al, Ga, Mn). The room temperature X-ray diffraction (RT-XRD), field emission scanning electron microscopy (FE-SEM), and energy dispersive spectroscopy (EDS) measurements highlight the crystal structure of the materials with excellent chemical homogeneity at the micro-scale. RT-XRD and Raman spectroscopy confirmed the formation of single-phase cubic spinel structures. However, the Mn-based sample exhibited tetragonal distortion. Magnetic measurements show remarkable variation in the magnetic properties: (Ni0.2Mg0.2Co0.2Cu0.2Zn0.2)MnO shows complex ferrimagnetic behavior, Al and Ga based diamond lattice (Ni0.2Mg0.2Co0.2Cu0.2Zn0.2)BO (B = Al and Ga) materials revealed extremely high magnetic frustration and absence of magnetic ordering down to 1.8 K, indicative of exotic frustrated state. Magnetic transitions (spin-glass like) are observed in (Ni0.2Mn0.2Co0.2Cu0.2Zn0.2)BO (B = Al and Ga) materials. Our study highlights the potential to finely tune the magnetic responses through compositional engineering, thus paving the way for the development of tailored magnetic materials for various applications.
高熵氧化物（HEOs）作为材料研究领域前景广阔的前沿技术，其最新进展引发了人们的极大兴趣，彻底改变了材料设计和性能的面貌。高熵氧化物具有出色的稳定性、引人入胜的功能特性以及无与伦比的设计灵活性，这些都得益于在这些材料中加入了多种阳离子。在这项研究中，我们成功稳定了几种新的高熵尖晶石氧化物，其成分为 (Ni0.2(Mg/Mn)0.2Co0.2Cu0.2Zn0.2)B2O4（B = Al、Ga、Mn）。室温 X 射线衍射（RT-XRD）、场发射扫描电子显微镜（FE-SEM）和能量色散光谱（EDS）测量结果表明，这些材料的晶体结构在微观尺度上具有极佳的化学均匀性。RT-XRD 和拉曼光谱证实了单相立方尖晶石结构的形成。然而，锰基样品表现出四方畸变。磁性测量显示磁性能存在显著差异：(Ni0.2Mg0.2Co0.2Cu0.2Zn0.2)Mn2O4 显示出复杂的铁磁行为，而基于铝和镓的金刚石晶格 (Ni0.2Mg0.2Co0.2Cu0.2Zn0.2)B2O4 (B = Al 和 Ga) 材料显示出极高的磁沮度，在低至 1.8 K 的温度下没有磁有序，表明存在奇异的沮度状态。在（Ni0.2Mn0.2Co0.2Cu0.2Zn0.2）B2O4（B = Al 和 Ga）材料中观察到了磁跃迁（类似自旋玻璃）。我们的研究强调了通过成分工程精细调节磁响应的潜力，从而为开发适用于各种应用的定制磁性材料铺平了道路。
{"title":"Structure, Raman spectroscopy, and magnetic properties of new Al, Ga, and Mn-based high entropy oxides","authors":"Neha Sharma , Sushanta Mandal , Sourav Marik","doi":"10.1016/j.ceramint.2024.09.170","DOIUrl":"10.1016/j.ceramint.2024.09.170","url":null,"abstract":"<div><div>Recent advancements in high entropy oxides (HEOs) have sparked significant interest as a promising frontier in materials research, revolutionizing the landscape of material design and properties. They exhibit outstanding stability, intriguing functional properties, and unparalleled design flexibility enabled by the inclusion of multiple cations in these materials. In this study, we successfully stabilized several new high entropy spinel oxides with compositions (Ni<sub>0.2</sub>(Mg/Mn)<sub>0.2</sub>Co<sub>0.2</sub>Cu<sub>0.2</sub>Zn<sub>0.2</sub>)B<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> (B = Al, Ga, Mn). The room temperature X-ray diffraction (RT-XRD), field emission scanning electron microscopy (FE-SEM), and energy dispersive spectroscopy (EDS) measurements highlight the crystal structure of the materials with excellent chemical homogeneity at the micro-scale. RT-XRD and Raman spectroscopy confirmed the formation of single-phase cubic spinel structures. However, the Mn-based sample exhibited tetragonal distortion. Magnetic measurements show remarkable variation in the magnetic properties: (Ni<sub>0.2</sub>Mg<sub>0.2</sub>Co<sub>0.2</sub>Cu<sub>0.2</sub>Zn<sub>0.2</sub>)Mn<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> shows complex ferrimagnetic behavior, Al and Ga based diamond lattice (Ni<sub>0.2</sub>Mg<sub>0.2</sub>Co<sub>0.2</sub>Cu<sub>0.2</sub>Zn<sub>0.2</sub>)B<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> (B = Al and Ga) materials revealed extremely high magnetic frustration and absence of magnetic ordering down to 1.8 K, indicative of exotic frustrated state. Magnetic transitions (spin-glass like) are observed in (Ni<sub>0.2</sub>Mn<sub>0.2</sub>Co<sub>0.2</sub>Cu<sub>0.2</sub>Zn<sub>0.2</sub>)B<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> (B = Al and Ga) materials. Our study highlights the potential to finely tune the magnetic responses through compositional engineering, thus paving the way for the development of tailored magnetic materials for various applications.</div></div>","PeriodicalId":267,"journal":{"name":"Ceramics International","volume":"50 22","pages":"Pages 48200-48209"},"PeriodicalIF":5.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142262654","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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