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Non-orthogonal FE model with stress smoothing for progressive damage analysis of shear pre-deformed 3D angle-interlock woven composites under compression

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International Journal of Mechanical sciences 2022年 232卷

作者： Wang, Bing Chen, Zhiming Fang, Guodong Meng, Songhe Center for Composite Materials and Structures Harbin Institute of Technology Harbin150001 China Science and Technology on Advanced Composites in Special Environments Key Laboratory Harbin Institute of Technology Building A Science Park of HIT No.2 Yi-Kuang Street Nan-Gang District Harbin150001 China Technical Center Shijiazhuang Haishan Industrial Development Corporation Shijiazhuang050208 China

3D angle interlock woven fabric usually needs to produce pre-deformation to meet the requirements of the complex shape of the target configuration. This cause the internal fabric angle to change, which makes it difficult to predict the mechanical properties and damage evolution. A novel non-orthogonal mesoscale finite element (FE) model considering local stress smoothing is proposed to predict the effective mechanical properties and reveal the damage evolution process of shear pre-deformed 3D angle-interlock woven composites under compressive load. The spurious stresses in the vicinity of the different material interface caused by the stepped block-like voxel boundaries are efficiently eliminated to improve the failure prediction accuracy. The predicted warp directional compressive stress-strain curves are good agreement with that of experiments, and the failure morphologies are verified by Scanning Electron Microscopy (SEM). The validated simulation model is further to investigate the effects of shear angle on the effective compressive stiffness and strength of 3D angle-interlock woven composites in different direction. And the effects of shear pre-deformation and stress smoothing on the damage and failure mechanisms are discussed. This study is great helpful of providing reliable guidance for analyzing and designing the pre-deformed 3D woven composite complex structures, such as aero-engine fan blades. © 2022

关键词： Composite materials

Highly Conductive MXene Film Actuator Based on Moisture Gradients

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Angewandte Chemie 2020年第33期132卷 14133-14137页

作者： Wang J. Liu Y. Cheng Z. Xie Z. Yin L. Wang W. Song Y. Zhang H. Wang Y. Fan Z. MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150001 China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology Harbin 150080 China

MXene (Ti3C2Tx) is a new 2D material with both hydrophilicity and high electrical conductivity, and it has shown promise in smart electronic devices. Reported herein is a homogeneous MXene film actuator with high electrical conductivity triggered by moisture gradients. The actuator is highly sensitive to moisture and undergoes deformation, with the maximum bending angle as high as 155° at a relative humidity difference of 65 %. Several analysis methods show that the humidity drive and large deformation of the MXene film occur in situ by asymmetric expansion of the bilayer structure. The combination of deformation and electrical conductivity makes this film applicable to flexible excavators, electrical switches, and other fields, applications that are difficult to achieve directly by using other 2D materials. More importantly, this work further expands the new application range of MXene materials and provides new opportunities for building the next generation of high-conductivity smart actuators. © 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

关键词： conducting materials materials science molecular electronics thin films titanium

Influence of pre-existing interfacial damage on the ballistic behavior of ceramic composite armor systems: An experimental and numerical analysis

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Thin-Walled Structures 2025年 215卷

作者： Shibao Wu Chaocan Cai Guanjie Wang Xiaojun Wei Zhonghai Xu Qingyu Peng National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology Harbin 150080 China Suzhou Research Institute of HIT Harbin Institute of Technology Suzhou 215104 China

In recent years, Ceramic Composite Armor Systems (CCAS) have gained extensive applications in protective configurations of various armored weapon platforms due to their exceptional ballistic behavior. Nevertheless, the integration of functional modules into cohesive interfaces for enhancing CCAS intelligence presents a technical paradox: such modifications inevitably induce pre-existing interfacial debonding/delamination defects that may adversely affect ballistic behavior. Using a simplified Al 2 O 3 /Carbon Fiber (CF)/Aramid Fiber (AF) composite armor configuration as a representative example, this work systematically examines through combined Ballistic Limit Test (BLT) and Finite Element Analysis (FEA) how pre-existing damage parameters (including location, area and quantity) at both Al 2 O 3 -CF and CF-AF interfaces influence critical ballistic behavior responses, especially the residual velocity, back face deformation, damage circumstance and its extension patterns, etc. The results of the FEA are validated with the experimental results. The key findings reveal that under equivalent damage areas with single pre-existing damage, interfacial debonding at the Al 2 O 3 -CF interface demonstrates more pronounced ballistic behavior degradation compared to the CF-AF interface defects. This detrimental effect exhibits amplification beyond critical damage tolerance thresholds. Under dual pre-existing damage conditions, the detrimental effects on the ballistic behavior of the CCAS exhibit significant dependence on damage area combination characteristics.

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A Meso-Scale Fem-Sph Adaptive Model and Simulations of Fabric Under Hypervelocity Impact

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SSRN 2023年

作者： Xu, Huadong Zhou, Jia Cao, Xu Yu, Dong Miao, Changqing National Key Laboratory of Science and Technology on Advanced Composites in Special Environment Harbin Institute of Technology Harbin150001 China School of Water Conservancy & Civil Engineering Northeast Agricultural University Harbin150001 China School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin150001 China

A meso-scale FEM-SPH adaptive model for fabric is developed to simulate hypervelocity impact (HVI) response between multiple fabrics and projectile. An anisotropic elastic-plastic constitutive equation coupled with the Mie-Grüneisen equation of state (EOS) is adopted to describe deviatoric deformation and strongly nonlinear volumetric compression induced by HVI. Considering the interaction of fabric with hierarchical structure and the evolution of impact-induce fragments, a meso-scale FEM-SPH adaptive mesh was created for woven fabrics by finite element-smoothed particle hydrodynamics (FEM-SPH) adaptive method. The meso-scale mesh involves modeling the fabric using a fiber bundles level architecture around the impact region and a yarn level architecture at far field regions. The proposed numerical model is validated by comparing to damaged morphologies and shielding performance of fabric specimens from HVI experiments at different impact velocity. The simulation results are compared with the Lagrangian FEM model, and the results show that the FEM-SPH adaptive method has better prediction ability for the movement and diffusion of impact-induced debris clouds. In addition, the yarn partition sensitivity analysis by difference meso-scale fabric model demonstrates that the agreement of the simulation and experimental results increases with the increasing of the number of fiber bundles in the yarn cross-section, and further indicate that the meso-scale model developed in this paper for fabric has a good capacity for describing the essential details of fibers bundles/yarns in fabric during HVI. © 2023, The Authors. All rights reserved.

关键词： Yarn

Cation-induced topical disordered niobium nickel oxide for robust hydrogen storage in magnesium hydride

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Journal of Magnesium and Alloys 2024年

作者： Li, Shuai Zhang, Liuting Wu, Fuying Li, Qian School of Energy and Power Instrumental Analysis Center Jiangsu University of Science and Technology Zhenjiang212003 China National Engineering Research Center for Magnesium Alloys College of Materials Science and Engineering Chongqing University Chongqing400044 China State Key Laboratory of Advanced Special Steel School of Materials Science and Engineering Shanghai University Shanghai200444 China

Catalytic doping is one of the economic and efficient strategies to optimize the operating temperature and kinetic behavior of magnesium hydride (MgH2). Herein, efficient regulation of electronic and structural rearrangements in niobium-rich nickel oxides was achieved through precise compositional design and niobium cation functionalized doping, thereby greatly enhancing its intrinsic catalytic activity in hydrogen storage systems. As the niobium concentration increased, the Ni-Nb catalysts transformed into a mixed state of multi-phase nanoparticles (composed of nickel and niobium-rich nickel oxides) with smaller particle size and uniform distribution, thus exposing more nucleation sites and diffusion channels at the MgH2/Mg interface. In addition, the additional generation of active Ni-Nb-O mixed phase induced numerous highly topical disordered and distorted crystalline, promoting the transfer and reorganization of H atoms. As a result, a stable and continuous multi-phase/component synergistic catalytic microenvironment could be constructed, exerting remarkable enhancement on MgH2's hydrogen storage performance. After comparative tests, Ni0.7Nb0.3-doped MgH2 presented the optimal low-temperature kinetics with a dehydrogenation activation energy of 78.8 kJ·mol−1. The onset dehydrogenation temperature of MgH2+10 wt% Ni0.7Nb0.3 was reduced to 198 °C and 6.18 wt% H2 could be released at 250 °C within 10 min. In addition, the dehydrogenated MgH2[sbnd]NiNb composites absorbed 4.87 wt% H2 in 10 min at 125 °C and a capacity retention rate was maintained at 6.18 wt% even after 50 reaction cycles. In a word, our work supplies fresh insights for designing novel defective-state multiphase catalysts for hydrogen storage and other energy related field. © 2024

关键词： Activation energy

Self-Healable, Super-Stretchable and Shape-Adaptive Triboelectric Nanogenerator Based on Double Cross-Linked Pdms for Electronic Skins

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SSRN 2022年

作者： Cai, Ya-Wei Wang, Gui-Gen Mei, Yi-Cheng Zhao, Da-Qiang Peng, Jia-Jian Sun, Na Zhang, Hua-Yu Han, Jie-Cai Yang, Ya Shenzhen Key Laboratory for Advanced Materials School of Materials Science and Engineering Harbin Institute of Technology Shenzhen518055 China Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and Sensor Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing101400 China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology Harbin150080 China School of Nanoscience and Technology University of Chinese Academy of Sciences Beijing100049 China

Self-powered triboelectric nanogenerators (TENG) have shown great potential in the field of electronic skin (E-skin). However, TENG is vulnerable to damage by frequent mechanical impacts during operation. In this work, a self-healable (≤ 2 h), super-stretchable (> 760%) and shape-adaptive TENG was designed as an E-skin to harvest energy and monitor human motion. The triboelectric layer is self-healing double-crosslinked polydimethylsiloxane (PDMS) prepared by adjusting the ratio of imine bonds to hydrogen bonds (H-bonds). The electrode layer is self-healable conductive composite prepared via the formation of H-bonds between MXene and lightly cross-linked PDMS. This TENG can be perfectly attached to the uneven human skin surface due to shape adaptability and can maintain original triboelectric performance after repeated damage. Also, our TENG can switch freely between single sensor and sensor arrays due to high self-healing efficiency, suggesting promising applications in E-skin and wearable device. © 2022, The Authors. All rights reserved.

关键词： Nanogenerators

Microstructural Evolution and Strain Hardening Behavior of a Duplex Fe−Mn−Al−C Lightweight Steel

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SSRN 2023年

作者： Lu, Hai-Tao Li, Da-Zhao Bai, Shao-Bin Chen, Yong-An Cao, Peng-Fei Xu, Teng-Fei Yan, Zhi-Jie School of Materials Science and Engineering North University of China Taiyuan030051 China School of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan030024 China School of Aerospace Engineering North University of China Taiyuan030051 China Shanxi Key Laboratory of Advanced Metal Materials for Special Environments Taiyuan China

The microstructure evolution and mechanical properties of Fe−27Mn−10Al−1C (wt.%) duplex lightweight steel have been investigated in this paper. As the solution temperature increased from 800 ℃ to 1000 ℃, the recrystallization occurs and the coarse intergranular κ-carbides that harmful to ductility are eliminated. In comparison, the 1000℃ solution-treated steel shows an excellent combination of ultimate tensile strength (UTS) of 917 MPa and total elongation (TE) of 56.6%. The corresponding microstructural results indicated that austenite with nano-sized κ-carbides and ferrite with B2/DO3 synergistically enhance the strength. Dynamic partitioning of strain among these phases during plastic deformation leads to a high initial strain hardening rate. With increasing strain, the refinement of slip bands and the sufficient formation of microbands in austenite, as well as the transformation of superdislocations to dislocation cells in ferrite maintain a stable level of strain hardening, which also significantly improves the ductility of the steel. Besides, the strain gradient at the austenite/ferrite interface promotes the evolution of dislocation structures in each phase, allowing the steel to exhibit excellent strain hardening behavior. © 2023, The Authors. All rights reserved.

关键词： Ferrite

Workability Optimization and Microstructure Regulation for a Multi-Angular Extrusion Process of Az80 Magnesium Alloy

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SSRN 2023年

作者： Su, Zexing Sun, Chaoyang Qian, Lingyun Liu, Chengzhi Zhang, Li Liu, Yanlian School of Mechanical Engineering North University of China Taiyuan030051 China Shanxi Key Laboratory of Advanced Metal Materials for Special Environments North University of China Taiyuan030051 China School of Mechanical Engineering University of Science and Technology Beijing Beijing100083 China Beijing Key Laboratory of Lightweight Metal Forming Beijing100083 China

Engineering stability control of microstructure evolution and precision forming is a key technical issue for the high-performance manufacturing of magnesium alloy components. In this paper, a fine-grain processing window was proposed for the workability optimization and microstructure control of AZ80 magnesium alloy. The hot activation energy map (AEM) and processing map (PM) were established to analyze the hot-working properties and microstructural mechanisms, respectively. The internal state variable (ISV) based finite element (FE) model was introduced to predict the evolutions of grain size and microstructure homogeneity with processing parameters during multi-angular extrusion process. The fine-grain processing window was used to form a magnesium alloy plate. Fine microstructure and good forming performance were obtained with the optimized processing parameters at the complete DRX domain. Forming at the processing instability domain shows flow defects and microstructure heterogeneity. The above research can be applied to the processing parameter optimization and microstructure regulation during hot forming processes of magnesium alloy. © 2023, The Authors. All rights reserved.

关键词： Magnesium alloys

Rational Design of Fe-Doped Mno2@C Hollow Nanocubes with Enhanced Microwave Absorption Performance

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SSRN 2023年

作者： Xu, Dongwei Shen, Zhihao Zhang, Mingju Li, Xinyuan Deng, Lu Ren, Yeqi Xiong, Xuhai Ma, Shuaijiang Guo, Xiaoqin Chen, Ping School of Material Science and Engineering Henan Key Laboratory of Aeronautical Materials and Application Technology Zhengzhou University of Aeronautics Zhengzhou450046 China Liaoning Key Laboratory of Advanced Polymer Matrix Composites Shenyang Aerospace University Shenyang110136 China Faculty of Engineering Huanghe Science & Technology University Zhengzhou450063 China State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian116024 China

The rational structural design and compositional merits as well as the synergistic coupling effect can break the properties of single material and broaden the microwave absorption band. Herein, the unique lightweight Fe-doped MnO2@C hollow nanocubes are rationally designed and successfully synthesized via a scalable wet chemical process and polydopamine coating followed by high-temperature calcination. By virtue of the unique structure and compositional merits, the synthesis of well-defined Fe-doped MnO2@C hollow nanocubes (Fe-MnO2@C-HNBs) displayed notable microwave absorption performance (MAP), simultaneously achieving ultrabroad bandwidth and strong absorption characteristics at low thickness of 2.3 mm (-41.02 dB and 5.86 GHz) and 2.7 mm (-38.20 dB and 8.08 GHz) with the filling content of 30 wt.%, respectively. The results further confirmed that the excellent microwave attenuation ability of the prepared Fe-MnO2@C-HNBs composites benefitted the special "air@core-shell" structure and heterointerface engineering as well as multi-component recombination. These results demonstrated that the as-obtained Fe-MnO2@C-HNBs could be attractive candidates for broadband microwave absorption materials. © 2023, The Authors. All rights reserved.

关键词： Manganese oxide