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Gradient C f /ZrB 2 -SiC composites integrating low-density, good mechanical properties and heat-resistant

Journal of Materials science & technology 2026年 242卷 156-165页

作者： Qiang Gao Ping Hu Yuxuan Xia Yuan Cheng Guangdong Zhao Jiaxin Feng Zibin Chen Xinghong Zhang National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Center for Composite Materials and Structures Harbin Institute of Technology Harbin 150080 China Beijing Power Machinery Institute The Third Academy of State-owned Aerospace Giant China Aerospace Science & Industry Corporation (CASIC) Beijing 100074 China School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

Ultra-high temperature ceramic composites (UHTCCs) with low density and exceptional heat resistance are essential for hypersonic vehicle applications, enabling increased payload capacity and higher Mach numbers. However, developing a fabrication process that enables UHTCCs with both lightweight and superior thermal protection performance is still a challenge. To tackle this problem, in this study, a combinatorial process of vibration-assisted slurry impregnation and polymer infiltration pyrolysis was developed to fabricate gradient lightweight C f /ZrB 2 -SiC composites, consisting of continuous carbon fiber fabric, ZrB 2 -SiC and a carbon aerogels (CAs) layer. The resulting composites exhibit a low density of (0.62–0.96 g cm −3 ) but excellent oxidation and ablation resistance, which can withstand ultrahigh temperatures between 2100 °C and 2500 °C. The porous C f /CAs layer, with a density of 0.38 g cm −3 and specific bending and compressive strengths of 43.47 MPa/(g cm −3 ) and 15.53 MPa/(g cm −3 ), respectively, provides both structural integrity and lightweight properties to the C f /ZrB 2 -SiC composite. Furthermore, the density of the composites can be precisely tailored by adjusting the thickness of the C f /ZrB 2 -SiC layer, allowing for customized fabrication to meet diverse service environment requirements. This flexibility highlights the adaptability of the combined processing techniques. The unique combination of controllable low-density properties and exceptional oxidation and ablation resistance endows gradient lightweight C f /ZrB 2 -SiC composites are promising as lightweight, ultra-high temperature thermal protection systems for hypersonic vehicle applications.

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Bioinspired Multi-Stimulus Responsive Mxene-Based Soft Actuator with Self-Sensing Function and Various Biomimetic Locomotion

SSRN

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SSRN 2023年

作者： Xu, Liangliang Zheng, Haowen Xue, Fuhua Ji, Qixiao Qiu, Changwen Yan, Qian Ding, Renjie Zhao, Xu Hu, Ying Peng, Qingyu He, Xiaodong National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Center for Composite Materials and Structures Harbin Institute of Technology Harbin150080 China Institute of Industry and Equipment Technology Hefei University of Technology Hefei230009 China

Although a series of outstanding achievements have been realized so far, developing soft actuators that can respond to various stimuli and simulate biological versatility (e.g., self-sensing function, diverse locomotion, etc.) is still a great challenge. Here, by utilizing internal stress generated spontaneously during the preparation process, an originally rolled MXene/polydimethylsiloxane (PDMS) bimorph soft actuator has been designed and fabricated. Based on the outstanding photothermal/electrothermal conversion efficiency and adjustable interlayer d-spacing change of Ti3C2Tx MXene, and the large thermal/chemical vapor expansion of crosslinked PDMS, this actuator can produce reversible large deformation under various forms of stimulus, including heat, light, electric, and n-hexane vapor. More importantly, microcracks can be formed spontaneously on the surface of MXene layer during the fabrication process of the actuator, which causes the resistance of MXene layer to be very sensitive to mechanical deformation. Based on this, a light-driven artificial tongue is fabricated, which not only mimic the ejection motion and catching prey behavior of the frog’s tongue, but also perceive the touching object. Moreover, a series of sophisticated biomimetic locomotion such as jumping, crawling, and self-oscillation all can be realized by using this soft actuator. Besides, the actuator with rolled initial structure can also be an intelligent gripper with low energy consumption. By doping Fe3O4 nanoparticles in PDMS matrix, the composite actuator can carry object to through complex maze in adjustable magnetic field without additional stimulation. This MXene-based actuator provides new insights in design of next generation of smart actuators with multi-functions and multiform motions. © 2023, The Authors. All rights reserved.

关键词： Magnetite

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Welding Process Parameters and Mechanical Properties of Carbon Fiber-Reinforced Thermoplastic composites: Experimental and Simulation Analysis

SSRN

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SSRN 2024年

作者： Wang, Bing Yu, Lin Li, Menglei Guo, Jiabao Ji, Chunming Hu, Jiqiang National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology Harbin150001 China Beijing Institute of Astronautical Systems Engineering Beijing100076 China AVIC Jonhon Optoelectronics Technology Co. Ltd. Luoyang471000 China

Based on the fusible welding characteristic of thermoplastic composites, this paper develops a resistance welding apparatus to investigate the influence of welding parameters on welding performance and determine optimal welding parameters. To apply numerical simulation to study the mechanical properties of welded composite structures, we propose a multiscale model that combines experiments and micromechanical models. The experiments provide the normal fracture toughness and the tangential mechanical properties of the welds, while the micromechanical model based on the fast Fourier transform (FFT) method and the phase field method (PFM) provides the normal strength of the welds, and cohesive elements are used to simulate the welds. The correctness of the results calculated by the proposed multiscale model is verified based on double cantilever beam (DCB) experiments and T-joint structures. And further investigating the influence of laminate thickness on DCB performance and the failure mechanism of T-joints under bending loads based on this multiscale model. © 2024, The Authors. All rights reserved.

关键词： Welds

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Rashba-like spin splitting around non-time-reversal-invariant momenta

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Physical Review B 2023年第23期107卷 235138-235138页

作者： L. L. Tao Jiayu Li Yuntian Liu Xianjie Wang Yu Sui Bo Song M. Ye. Zhuravlev Qihang Liu School of Physics Harbin Institute of Technology Harbin 150001 China Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology Shenzhen 518055 China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology Harbin 150001 China St. Petersburg State University St. Petersburg 190000 Russia

The ubiquitous Rashba spin splitting occurring around time-reversal-invariant momenta (TRIM) reflects the fundamental interplay between spin-orbit coupling (SOC) and crystalline symmetry. Unexpectedly, recent measurements reveal novel Rashba spin splitting around the momenta lacking time-reversal symmetry (non-TRIM), whose mechanism remains elusive. Here, we theoretically elucidate the microscopic origin of Rashba spin splitting around non-TRIM and identify the design principles for its appearance. Conventionally, a Zeeman-like spin splitting dominates around non-TRIM due to the broken time-reversal symmetry and diminishes the Rashba-like features. Our results show that the Bloch wave function with specific orbital representation at certain non-TRIM could eliminate the first-order SOC effect. As a result, the corresponding little group hosts a type of quasisymmetry that commutes with the dominating SOC Hamiltonian, leading to a tiny SOC gap and helical spin texture. Furthermore, such a quasi-symmetry-induced tiny gap could manifest large Berry curvature, which is desirable for various topological applications. Our work expands the concept of Rashba physics beyond the conventional TRIM scenario, paving an avenue for designing novel spin-splitting materials through the cooperation of symmetry and orbital engineering.

关键词： Crystal symmetry Rashba coupling Spin-orbit coupling Interfaces Density functional calculations

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Ultra-fast synthesis and thermodynamic analysis of MoAlB by self-propagating high temperature combustion synthesis

arXiv

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arXiv 2022年

作者： Yin, Hang He, Xiaodong Song, Guangping Yu, Yongdong Zheng, Yongting Bai, Yuelei National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Centre for Composite Materials and Structures Harbin Institute of Technology Harbin150080 China

MoAlB as a typical member of the MAB phases has attracted much growing attention due to its unique properties. However, the low production of MoAlB powders limits its further development and potential applications. To respond this challenge, the ultra-fast preparation of high-purity MoAlB powders is achieved in a few seconds by self-propagating high temperature combustion synthesis (SHS) using the raw powder mixture at the atomic ratio of 1Mo/1.3Al/1B. The reaction mechanism in SHS process was obtained by analyzing the corresponding composition changes of starting materials. Furthermore, the thermodynamic prediction for the SHS reaction of Mo + (1+ y) Al + B = MoAlB + yAl is consistent with the present experiments, where the preparation of MoAlB also conforms to two common self-propagating conditions of SHS. Enthalpy vs temperature curve shows that the adiabatic temperature of the reaction decreases with increasing the amount of excuse Al, but increases when pre-heating the reactants. The thermodynamic calculation method also provides a new idea for the preparation of other MAB phases by SHS. © 2022, CC BY-NC-SA.

关键词： Temperature

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Microstructural Formation and Evolution of Near-Eutectic Al2o3-Zro2 Powders Prepared by a Rapid Cooling Technique: An Extended Composition Range for Complete Eutectic Microstructures Without Primary Dendrites

SSRN

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SSRN 2022年

作者： Yuan, Yuchen Yu, Wanjun Zheng, Yongting Yu, Yongdong Liu, Xudong Yin, Hang National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Center for Composite Materials and Structures Harbin Institute of Technology Harbin150080 China

Regulation of eutectic compositions is a difficult challenge due to the limited formation range of this microstructure. Al2O3-ZrO2 powders were successfully prepared through a modified high-temperature melt-assisted air atomization technique. The high-temperature melt (3500 K) was obtained based on the exothermic reaction between Al and O2, which was subsequently atomized and quenched to form composite powders. Eutectic colonies with nanolamellae (62–79 nm) were observed in the as-prepared Al2O3-(28–58 mol%) ZrO2 powders. Importantly, the powders with ZrO2 contents of 38 mol% and 42 mol% showed complete eutectic microstructures without primary dendrites, which indicated an extended obtainable range deviating by ~4.9 mol% from the eutectic composition (CE). The microstructural formation mechanism was discussed based on solidification behavior analysis. Furthermore, the evolution of the microstructure and phase in Al2O3-42 mol% ZrO2 powders was investigated. This work provides a reference for the composition regulation of oxide eutectics. © 2022, The Authors. All rights reserved.

关键词： Eutectics

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Preparation of Brittle Ito Microstructures Using Laser-Induced Forward Transfer technology

SSRN

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SSRN 2024年

作者： Sun, Chunqiang Wang, Zhuochao Cao, Wenxin Gao, Gang Yang, Lei Han, Jie-Cai Zhu, Jiaqi National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology Harbin150080 China Zhengzhou Research Institute Harbin Institute of Technology Zhengzhou450000 China Key Laboratory of Micro-Systems and Micro-Structures Manufacturing Ministry of Education Harbin Institute of Technology Harbin150080 China

The performance of transparent conductive microstructures plays a significant role in determining the device efficiency. The fabrication of ITO microstructures on the flexible optoelectronic devices remains challenging because of the high-temperature processing requirements and brittleness of the ceramic material. This paper highlights a three-dimensional microfabrication technique that combines sacrificial layer etching and laser-induced transfer. By studying the donor material thickness and the laser energy density, control of the sacrificial layer transfer thrust was achieved to yield an optimal microstructure performance. Different shapes of ITO transparent conductive microstructures were fabricated on polydimethylsiloxane (PDMS) surfaces, demonstrating structural integrity, visible light transmittances >90%, and resistivities of ≤8×10−⁴ Ω·cm. Finite element analysis was employed to simulate the impact transfer of the donor material onto the receiving substrate, thereby elucidating the energy-absorbing protective role of the flexible PDMS layer. Effective control of the transfer force was identified as a crucial factor in achieving the successful transfer of brittle films. This high-precision and rapid array processing approach meets the demands of automated batch manufacturing, indicating its potential for use in patterned processing on flexible substrates, as an alternative to lithographic techniques. This technique could be applied in the preparation of electronic skins and flexible devices. Additionally, for the first time, a 3×3 pixel resistive array sensor was integrated on a Ag nanowires/PDMS surface, demonstrating array pressure-sensing capabilities at pressures of 0–80 kPa. This study represents a significant step towards the development of multifunctional flexible optoelectronic devices. © 2024, The Authors. All rights reserved.

关键词： Polydimethylsiloxane

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Polarization Multiplexing Graphene-Based Coding Metasurfaces For Flexible Wavefront Manipulation And Polarization of Terahertz Beam

SSRN

引用

SSRN 2023年

作者： He, Xunjun Lu, Jinliang Jiang, Jiuxing Yao, Yongtao Zhang, Ying School of Electrical and Electronic Engineering Harbin University of Science and Technology Harbin150080 China College of Science Harbin University of Science and Technology Heilongjiang150080 China National key laboratory of science and technology on advanced composites in special environments Harbin Institute of Technology Harbin150080 China

Recently, the wavefront control devices based on terahertz metasurfaces have drawn enormous attention in next-generation (6G) communication applications. Generally, these devices achieve dynamic wavefront control by integrating the metasurfaces with traditional active materials. However, most existing devices suffer from limitations such as single polarization mode of incident waves and intrinsic properties of the active materials, which hinder their developments and applications. To address these challenges, herein, we design graphene-based reflection coding metasurfaces for active wavefront control. The coding meta-atom is composed of a graphene split ring resonator, a dielectric layer, and a metal ground plate. Furthermore, by rotating the coding meta-atom, an independent 2π phase coverage may be obtained for CP or LP illuminations, enabling the polarization multiplexing. Based on the vortex phase profile, a proof-of-concept metasurface (MS-1) is constructed to generate different wavefront responses. By altering the polarization mode of incident waves and Fermi level of coding regions, these wavefronts can be actively switched between a vortex beam, multi-beam, and specular reflection beam. Additionally, according to the parabolic phase profile, another metasurface (MS-2) is developed to create a tunable metalens, allowing for active control over its focusing intensity and focal depth by adjusting the Fermi level of graphene. Therefore, these wavefront-controlled metasurfaces have high capacity and integration due to polarization multiplexing and active modulation, making them highly promising for potential applications in terahertz communications. © 2023, The Authors. All rights reserved.

关键词： Graphene

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Strong convergence of the adaptive Milstein method for nonlinear stochastic differential equations with piecewise continuous arguments

arXiv

引用

arXiv 2025年

作者： Zhang, Yuhang Song, Minghui Zhu, Jiaqi School of Astronautics Harbin Institute of Technology Harbin150080 China Zhengzhou Research Institute Harbin Institute of Technology Zhengzhou450000 China School of Mathematics Harbin Institute of Technology Harbin150001 China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology Harbin150080 China

In this work, an adaptive time-stepping Milstein method is constructed for stochastic differential equations with piecewise continuous arguments (SDEPCAs), where the drift is one-sided Lipschitz continuous and the diffusion does not impose the commutativity condition. It is widely recognized that explicit Euler or Milstein methods may blow up when the system exhibits superlinear growth, and modifications are needed. Hence we propose an adaptive variant to deal with the case of superlinear growth drift coefficient. To the best of our knowledge, this is the first work to develop a numerical method with variable step sizes for nonlinear SDEPCAs. It is proven that the adaptive Milstein method is strongly convergent in the sense of Lp, p ≥ 2, and the convergence rate is optimal, which is consistent with the order of the explicit Milstein scheme with globally Lipschitz coefficients. Finally, several numerical experiments are presented to support the theoretical analysis. Copyright © 2025, The Authors. All rights reserved.

关键词： Stochastic systems

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Superbroad-band actively tunable acoustic metamaterials driven from poly(ethylene terephthalate)/carbon nanotube nanocomposite membranes

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Nano Research 2021年第1期14卷 100-107页

作者： Ying Li Wen Ning Qingyu Peng Minglong Yang Dongyi Lei Siyao Guo Peng Liu Kaili Jiang Xiaodong He Yibin Li School of Civil Engineering Qingdao University of TechnologyQingdao 266033China National Key Laboratory of Science and Technology for National Defence on Advanced Composites in special Environments Harbin Institute of TechnologyHarbin 150080China State Key Laboratory of Low-Dimensional Quantum Physics Department of Physics&Tsinghua-Foxconn Nanotechnology Research CenterTsinghua University&Collaborative Innovation Center of Quantum MatterBeijing 100084China Shenzhen STRONG Advanced Materials Institute Ltd.Corp Shenzhen 518000China

Actively tunable acoustic metamaterials have attracted ever increasing ***,their tunable frequency range is quite narrow(tens of Hz)even under ultrahigh applied voltage(about 1,000 V).Here,we report a superbroad-band actively tunable acoustic metamaterials with the bandwidth over 400 Hz under a low *** the actively tunable acoustic metamaterials,the acoustic membrane is a laminated nanocomposite consisting of a poly(ethylene terephthalate)(PET)and super-aligned carbon nanotube(CNT)drawn from CN T forest *** laminated nanocomposite membrane exhibits adjustable acoustic properties,whose modulus can be adjusted by applying external electric *** maximum frequency bandwidth of PET/CN T nanocomposite membrane reaches 419 Hz when applying an external DC voltage of 60 *** actively tunable acoustic metamaterials with superbroad-band and lightweight show very promising foreground in noise reduction applications.

关键词： poly(ethylene terephthalate)/carbon nanotube nanocomposite membrane active control acoustic metamaterials noise reduction

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