检索结果-内蒙古大学图书馆

Ductile-Brittle Transition Mechanism of Highly-Oriented 3c-Sic in Elid

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Li, Hengyi Xu, Qingfang Zhang, Chitengfei Yang, Meijun Tu, Rong Zhang, Song Hubei Longzhong laboratory Xiangyang441000 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China Wuhan University of Technology China

Compared with sintered silicon carbides (SiC), highly-orientated 3C-SiC by CVD methods boasts out-of-plane orientation uniformity, which ensures that such materials produce lower surface damage. Through the ELID grinding technique, the differences in grinding behaviors between and -orientated 3C-SiC were investigated. Both highly-orientated 3C-SiC exhibited a grinding surface where brittle and ductile removal coexisted. Specifically, brittle removal regions were observed at grain boundaries, while ductile removal regions were observed within the grains. Further indentation experiments between the two 3C-SiC show that -oriented 3C-SiC displayed a larger critical cut depth of 28.99 nm, with 1.5 times higher than that of -oriented 3C-SiC. The larger critical depth of cut contributes to more ductile removal regions with only a few brittle pits in the -oriented 3C-SiC grinding surface. In addition, the subsurface deformation of -oriented 3C-SiC was characterized by the presence of amorphous zones, dislocations and stacking faults. In contrast to the -oriented, the -oriented 3C-SiC tends to exhibit a brittle removal mode dominated by pits and cracks at the twin boundaries, as its pre-existing twins hinder the dislocation glide, resulting in stress concentration and thus forming cracks. © 2024, The Authors. All rights reserved.

关键词： Silicon carbide

Rodent enamel-inspired hydroxyapatite nanocomposites with Fe 3+ -rich amorphous intergranular phases

学校读者我要写书评

暂无评论

Journal of materials Research and technology 2025年 36卷 7423-7432页

作者： Shenye Chen Zhengjian Su Bingyu Xue Benxi Xu Yafei Cheng Kun Wang Yidi Li Zhengyi Fu Hubei Longzhong Laboratory Xiangyang 441000 PR China School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 PR China State Key Laboratory of Precision Blasting Jianghan University Wuhan 430056 PR China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 PR China

Rodent enamel is primarily composed of hydroxyapatite (HAP) nanowires and Fe 3+ -rich amorphous intergranular phases (AIP). Inspired by rodent tooth enamel, this study successfully formed a layer of Fe 3+ -rich AIP on the outer layer of HAP nanowires by ion exchange between Fe 3+ and Ca 2+ within the HAP lattice. The thermal stability of Fe-HAP nanowires with Fe 3+ -rich AIP was enhanced. By bi-directional freezing of Fe-HAP nanowires with polyvinyl alcohol (PVA), rodent enamel-like nanocomposites (Fe-HEN) were obtained. Owing to the reinforcing and toughening effect of Fe 3+ -rich AIP, Fe-HEN exhibited a hardness of 1.66 ± 0.23 GPa, a Young's modulus of 48.8 ± 6.7 GPa in the longitudinal direction, as well as a hardness of 1.38 ± 0.16 GPa and a Young's modulus of 40.2 ± 3.0 GPa in the transversal direction. The flexural strength of the sample reached 153.5 ± 5.0 MPa, which is 2.9 times higher than that of samples without AIP, surpassing the performance of natural rodent enamel. The compressive strength reached 205 ± 4.3 MPa, representing a 1.5-fold increase over the sample without AIP and comparable to that of natural enamel. Compared to samples without AIP, Fe-HEN exhibits superior fracture toughness and crack deflection, better corrosion resistance, owing to the reinforcing effect of Fe 3+ -rich AIP at nanowire interfaces. This study demonstrates the incorporation of amorphous reinforced structures into the tooth enamel-like materials via ion exchange, offering a promising strategy for the development of high-performance multiscale composites.

关键词： Hydroxyapatite nanowires Amorphous intergranular phases Enamel-like nanocomposites Ion exchange Rodent enamel-inspired

Capacity Optimization of Hybrid Energy Storage System Based on Hysteresis Energy Management Strategy

学校读者我要写书评

暂无评论

Capacity Optimization of Hybrid Energy Storage System Based ...

IEEE Annual Southern Power Electronics Conference (SPEC)

作者： Wenlong Yang Minwang Wang Wenchao Zhu Changjun Xie Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of Technology Wuhan China School of Automation Wuhan University of Technology Wuhan China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan China

ISBN: (数字)9798350351156

ISBN: (纸本)9798350351163

This study improves the hydrogen energy module of the hydrogen-electric coupling system and proposes a hybrid hydrogen storage system structure based on Proton Exchange Membrane Electrolyzer (PEMEL), Alkaline Electrolyzer (ALKEL), and Proton Exchange Membrane Fuel Cell (PEMFC). Considering component startup and shutdown characteristics, dynamic operation, component degradation, and their impact on system reliability, a novel triple-hysteresis energy management strategy is proposed. The comprehensive optimization objectives include minimizing the Levelized Cost of Energy (LCOE), the Loss of Power Supply Probability (LPSP), and the Wind-Solar Curtailment to Load Energy Ratio (WSCLR). The optimal capacity configuration of the hybrid renewable energy system under the new energy management strategy was determined. The performance of the proposed strategy was analyzed and compared over short-term (1 year) and long-term (20 years) operations. The results indicate that the WSCLR of the ALKEL and PEMEL coupled structure is reduced by 83.3% compared to a single ALKEL system, and the LCOE and WSCLR are reduced by 2.1% and 3.5%, respectively, compared to a single PEMEL system. Compared to traditional energy management strategies, the new energy management strategy can reduce the LCOE, WSCLR, and LPSP by 2.7%, 45.0%, and 79.1%, respectively, over a 20-year long-term operation.

关键词： Protons Renewable energy sources System performance Hydrogen Lithium batteries Resource management Reliability Energy management Optimization Hysteresis

[email protected] structured fillers for increasing dielectric constant and suppressing dielectric loss of PVDF-based composite films

学校读者我要写书评

暂无评论

Ceramics International 2022年第16期48卷 22691-22698页

作者： Dajun Hou Jing Zhou Wen Chen Pengchao Zhang Jie Shen Zelang Jian State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 PR China

High dielectric constant polymer dielectrics have attracted a great deal of attention in flexible electronics. However, it appears to be a paradox for polymer dielectrics that the enhancement of their dielectric constant often comes along with the increase of dielectric loss. Hence, we reported [email protected] shell structured filler/poly(vinylidene fluoride) (PVDF) composites to overcome this paradox. The hybrid filler with BaTiO 3 (BT) as the core, conductive carbon as the inner shell, and insulating polydopamine (PDA) as the outer shell was synthesized. As a result, the [email protected] @PDA/PVDF composites at the filler content of 11 vol% exhibit an outstanding dielectric performance with a dielectric constant of 45 and a dielectric loss of 0.053 at 10 3 Hz. This phenomenon can be attributed to the increased interfacial polarization induced by the inner carbon shell and the conductive paths blockade caused by the outside PDA shell inside the [email protected] @PDA/PVDF composites. This work reveals that rational design of [email protected] shell structured hybrid fillers maybe a promising way to optimize the overall dielectric performance of the PVDF-based composites.

关键词： [email protected] Dielectric constant Dielectric loss PVDF-based composites

Long-term Unsupervised Prediction of Proton Exchange Membrane Fuel Cells Considering Voltage Recovery

学校读者我要写书评

暂无评论

Long-term Unsupervised Prediction of Proton Exchange Membran...

IEEE Annual Southern Power Electronics Conference (SPEC)

作者： Jiarui Xue Wenchao Zhu Changjun Xie School of Automation Wuhan University of Technology Wuhan China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan China Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of Technology Wuhan China

ISBN: (数字)9798350351156

ISBN: (纸本)9798350351163

Predicting degradation behavior is both challenging and essential for the prognosis and health management of proton exchange membrane fuel cells (PEMFCs). This paper considers the voltage recovery phenomenon that occurs during the frequent start-stop cycles of PEMFCs and proposes a voltage recovery (VR) model to calculate and predict the value of voltage recovery. FC1 is used as a reference sample with fully known degradation, while FC2 is considered a cell in the degradation process. A Gate Recurrent Unit (GRU) neural network is employed to learn the mapping relationship between FC1 and FC2 and predict the state of health (SOH) of FC2. Finally, the prediction results from the VR model and the GRU neural network are combined to obtain the final prediction outcome. The proposed hybrid method effectively improves prediction performance by combining the local dynamic characteristics predicted by the VR model with the overall degradation trend predicted by the data-driven method, offering both improved accuracy and practical significance.

关键词： Degradation Protons Accuracy Neural networks Fuel cells Predictive models Market research Data models Power electronics Prognostics and health management

Scalable Assembly of Layered Dielectric Nanocomposites Filled with Perovskite Nanosheets for Flexible Electronics

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Fu, Si Ren, Lele Wang, Jian Liu, Hexing Zhang, Pengchao Shen, Zhonghui Zhang, Xin Tu, Rong Zhang, Song Nan, Ce-Wen Li, Bao-Wen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China School of Materials Science and Engineering Wuhan University of Technology Wuhan430070 China State Key Lab of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing100084 China

Polymer-based dielectrics have attracted much attention in the field of flexible electronics due to their excellent flexibility, dielectric and mechanical properties. However, the rational design of nanofiller-polymer nanocomposite for improving dielectric and mechanical properties remains challenging. Herein, layered nanocomposites filled with high-κ Ca2Nb3O10 perovskite nanosheets were fabricated via shear-flow induced alignment of nanosheets. The hierarchical structure and good dispersion of nanosheets endowed the layered nanocomposites with an outstanding modulus of 12.7 GPa and toughness of 1.8 MJ/m3. Meanwhile, the layered nanocomposites exhibited a high dielectric constant of 14.7, a low dielectric loss of 4.2%, and low leakage current density -7 A/cm2. The layered high-κ nanocomposites designed in this work will have broad application prospects in th flexible electronics. © 2024, The Authors. All rights reserved.

关键词： Perovskite

Structural Evolution and Thermoelectric Performance in (Gete)M(Sb2te3)N Compounds

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Chen, Shuo Liu, Keke Luo, Tingting Liao, Lin Yang, Zhen Zhong, Shenlong Wu, Jinsong Su, Xianli Poudeu, Pierre Ferdinand Poudeu Zhang, Qingjie Tang, Xinfeng State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China Department of Materials Science and Engineering University of Michigan Ann ArborMI48109 United States

Exploring the relationship between crystal structure and thermoelectric performance is a pivotal topic in the thermoelectric field. In this study, we have conducted a comprehensive investigation on the correlation between the structural evolution of (GeTe)m(Sb2Te3)n pseudo-binary system and the thermoelectric properties. The proportion of van der Waals bonds increase with the rising Sb2Te3 content, resulting in an increase in the anisotropy of the electrical conductivity and a decrease in the average sound velocity. Additionally, the cation sites in the crystal lattice of these compounds exhibit a mixed occupancy of Ge/Sb atoms, although the cation sites adjacent to the van der Waals gaps are predominantly occupied by Sb atoms. The ultra-low lattice thermal conductivity of the GST124 and GST147 compounds is mainly attributed to the high concentration of van der Waals bonds and enhanced phonon scattering arising from Ge/Sb mixed cation occupancy and high density of defect structures. The high electrical conductivity combined with the low lattice thermal conductivity enables GST124 and GST147 compounds to achieve a maximum ZT value of 0.56 and 0.57, respectively. Higher thermoelectric performance can be achieved through optimization of the microstructure as well as the carrier concentration. © 2024, The Authors. All rights reserved.

关键词： Anisotropy

通过表面终止化学设计实现高度可逆的锌金属阳极

学校读者我要写书评

暂无评论

Science Bulletin 2023年第23期68卷 2993-3002,M0005页

作者：刘宇陈树麟袁豪熊方宇刘琴安永康张建勇吴璐孙建国 Yong-Wei Zhang 安琴友 John Wang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Department of Materials Science and Engineering National University of SingaporeSingapore 117574Singapore Institute of High Performance Computing Agency for ScienceTechnology and Research(A*Star)Singapore 138632Singapore Institute of Materials Research and Engineering(IMRE) Agency for ScienceTechnology and Research(A*Star)Singapore 138634Singapore

锌表面自然形成的非均匀氧化层(ZnO)会与电解液发生反应形成Zn_(4)(OH)_(6)SO_(4)·xH_(2)O(ZSH)副产物,导致锌负极表面非均匀沉积,从而阻碍水性锌离子电池实际应用.为了排除氧化层分布形式的影响,本文利用表面终止化学设计策略在... 详细信息

锌表面自然形成的非均匀氧化层(ZnO)会与电解液发生反应形成Zn_(4)(OH)_(6)SO_(4)·xH_(2)O(ZSH)副产物,导致锌负极表面非均匀沉积,从而阻碍水性锌离子电池实际应用.为了排除氧化层分布形式的影响,本文利用表面终止化学设计策略在锌负极表面制备了一层完全氧化的ZnO层,研究发现锌负极均匀分布的ZnO层会原位演化形成致密的ZSH功能层.均匀且致密的ZSH能够有效隔绝电解液的腐蚀,从而有效提高锌负极界面的稳定性.此外,ZSH(002)晶面边缘的不饱和悬空键(如-O)更容易和Zn(H_(2)O)_(6)^(2+)结构中的锌离子形成强Zn-O键,可以促进Zn(H_(2)O)_(6)^(2+)的脱溶剂化和锌离子沿边扩散,实现了高度可逆的锌沉积行为并限制了副反应.基于此,本文提出与“表面脱水-晶体通道转移”机制明显不同的“边缘脱水-沿边缘转移”锌离子输运新机制.更重要的是,基于此组装的全电池显示出高循环稳定性(超过1000次循环)和高库仑效率(99.07%),验证了其潜在的实际应用价值.

关键词： Zn-O termination Zn Anode Solid electrolyte interphase Dendrite-free Zn ion battery

Regulation of Dynamic Recrystallization in p-Type Bi2Te3-Based Compounds Leads to High Thermoelectric Performance and Robust Mechanical Properties

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Chen, Shuo Luo, Tingting Yang, Zhen Zhong, Shenlong Su, Xianli Yan, Yonggao Wu, Jinsong Poudeu, Pierre Ferdinand Poudeu Zhang, Qingjie Tang, Xinfeng State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China Department of Materials Science and Engineering University of Michigan Ann ArborMI48109 United States

Bi2Te3-based bulk materials are the best commercially available thermoelectric materials for near room temperature applications. However, the poor mechanical properties of zone melting material and inferior thermoelectric performance of powder metallurgical material restrict their large scale deployment. In this study, p-type Bi₂Te₃-based materials were prepared using the hot extrusion technique, and the underlying mechanisms for microstructure evolution were revealed. The hot extrusion speed significantly impacts the strain rate, an indicator to modulate the dynamic recrystallization (DRX) and grain growth, thereby effectively regulating the microstructures of samples. For the sample extruded at a speed of 1.0 mm min-1, the refined grain with an average grain size of 1.53 μm and an orientation factor F(110) of 0.28 is achieved. This highly textured structure and high-density low-angle boundaries (LAGBs) maintain the high carrier mobility of 264 cm2 V-1 s-1, comparable with the zone melting sample. In contrast, increasing grain boundaries, dislocations, and inherent point defects intensifies the phonon scattering and suppresses the lattice thermal conductivity to 0.73 W m-1 K-1. All these contribute to a practical high ZT value of 1.1 at room temperature. Moreover, the fine grains and high-density dislocations ensure robust mechanic properties with a compressive strength of 189 MPa and a bending strength of 139 MPa, which is a guarantee for the successful cutting of microparticles with dimensions of 100 × 100 × 200 μm3. The fabrication of high-quality materials with both high thermoelectric performance and strong mechanical properties paves the way for the miniaturization of thermoelectric modules. © 2024, The Authors. All rights reserved.

关键词： Textures