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Wideband mid-infrared thermal emitter based on stacked nanocavity metasurfaces

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International Journal of Extreme Manufacturing 2022年第1期4卷 133-141页

作者： Tun Cao Meng Lian Kuan Liu Xianchao Lou Yaoming guo dongming guo School of Optoelectronic Engineering and Instrumentation Science Dalian University of TechnologyDalianPeople’s Republic of China Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalianPeople’s Republic of China

Efficient thermal radiation in the mid-infrared(M-IR)region is of supreme importance for many applications including thermal imaging and sensing,thermal infrared light sources,infrared spectroscopy,emissivity coatings,and camouflage.The ability to control light makes metasurfaces an attractive platform for infrared applications.Recently,different metamaterials have been proposed to achieve high thermal radiation.To date,broadening the radiation bandwidth of a metasurface emitter(meta-emitter)has become a key goal to enable extensive applications.We experimentally demonstrate a broadband M-IR thermal emitter using stacked nanocavity metasurface consisting of two pairs of circular-shaped dielectric(Si;N;)–metal(Au)stacks.A high thermal radiation can be obtained by engineering the geometry of nanocavity metasurfaces.Such a meta-emitter provides wideband and broad angular absorptance of both p-and s-polarized light,offering a wideband thermal radiation with an average emissivity of more than 80%in the M-IR atmospheric window of 8–14μm.The experimental illustration together with the theoretical framework establishes a basis for designing broadband thermal emitters,which,as anticipated,will initiate a promising avenue to M-IR sources.

关键词： mid-infrared wideband perfect thermal radiation surface plasmon resonance metasurface nanocavity

Special issue： Near-net shaping technology

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Frontiers of Mechanical Engineering 2018年第1期13卷 1-2页

作者： Dequn LI dongming guo Qingxue HUANG Yanchun LOU State Key Laboratory of Material Processing and Die & Mold Technology Huazhong University of Science and Technology Wuhan 430074 China Key Laboratory for Precision & Non-traditional Machining of Ministry of Education Dalian University of Technology Dalian 116024 China Heavy Machinery Engineering Research Center of Education Ministry Taiyuan University of Science and Technology Taiyuan 030024 China Shenyang Research Institute of Foundry Shenyang 110022 China

Near-net shaping is an efficient, economical and environmentally-friendly approach to manufacture products which are very close to the final shape, reducing the need for surface finishing. It has become more and more important to use raw materials and energy in an optimal way. Near-net shaping technology has attracted increasing attention in both academic and industrial communities, especially in China, because China has become the world＇s largest regional market for main material forming methods, such as casting, forging and injection molding. The main objective of this special issue in Frontiers of Mechanical Engineering is to bring together the leading ideas, experience and research results of academic scientists and researchers on various aspects of near-net shaping technology. This special issue contains eleven papers contributed by prestigious experts from different countries, including four reviews and seven research articles. These papers cover a broad area of the near-net shaping technology,

关键词： Injection molding casting-forging Material forming raw material Forged Energy sources Casting Surface finish

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高性能制造:设计与制造的协同机制

机械工程学报 2024年第1期60卷 2-12页

作者：宋学官李昆鹏胡正国郭东明大连理工大学机械工程学院大连116024

高性能制造,是由以几何精度为主的制造上升到以产品性能的精准保证为目标的制造,其作为推动我国装备制造业升级的引擎,以及引领传统制造理念提升的旗帜,对国家装备产业的发展具有十分重要的意义。高性能制造理论指出,传统的装备制造流... 详细信息

高性能制造,是由以几何精度为主的制造上升到以产品性能的精准保证为目标的制造,其作为推动我国装备制造业升级的引擎,以及引领传统制造理念提升的旗帜,对国家装备产业的发展具有十分重要的意义。高性能制造理论指出,传统的装备制造流程形成了设计、制造、服役等严格的上下游关系,一定程度上了推动了多任务协作能力,提高了装备制造的效率。然而,不容忽视的事实是,这种设计、制造的单向串行模式人为割裂了设计环节与制造环节的耦合作用,在提高制造效率的同时,亦不可避免地制约了高端装备性能的进一步提升。作为高性能制造理论的重要组成部分,针对上述设计、制造之间的耦合作用,展开了进一步的讨论。首次采用Karush-Kuhn-Tucker最优性条件,从数学角度定量定式的揭示了传统设计制造“不协同”的根源所在,并针对这些不足,给出串行、并行和循环模式的高性能制造解决方案和求解方法。为打破我国高端装备/零部件的高性能制造瓶颈,进一步推动我国高端装备高性能制造的发展提供了理论与技术参考。

关键词：高端装备/零部件高性能制造设计与制造协同并行模式循环模式

Hole quality in longitudinal–torsional coupled ultrasonic vibration assisted drilling of carbon fiber reinforced plastics

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Frontiers of Mechanical Engineering 2020年第4期15卷 538-546页

作者： guofeng MA Renke KANG Zhigang DONG Sen YIN Yan BAO dongming guo Key Laboratory for Precision and Non-Traditional Machining of Ministry of Education Dalian University of TechnologyDalian 116024China

Carbon fiber reinforced plastic (CFRP) composites are extremely attractive in the manufacturing of structural and functional components in the aircraft manufacturing field due to their outstanding properties, such as good fatigue resistance, high specific stiffness/strength, and good shock absorption. However, because of their inherent anisotropy, low interlamination strength, and abrasive characteristics, CFRP composites are considered difficult-to-cut materials and are prone to generating serious hole defects, such as delamination, tearing, and burrs. The advanced longitudinal–torsional coupled ultrasonic vibration assisted drilling (LTC-UAD) method has a potential application for drilling CFRP composites. At present, LTC-UAD is mainly adopted for drilling metal materials and rarely for CFRP. Therefore, this study analyzes the kinematic characteristics and the influence of feed rate on the drilling performance of LTC-UAD. Experimental results indicate that LTC-UAD can reduce the thrust force by 39% compared to conventional drilling. Furthermore, LTC-UAD can decrease the delamination and burr factors and improve the surface quality of the hole wall. Thus, LTC-UAD is an applicable process method for drilling components made with CFRP composites.

关键词： longitudinal–torsional coupled ultrasonically drilling CFRP thrust force hole quality

Smoothed-Particle Hydrodynamics Investigation on Brittle-Ductile Transition of Quartz Glass in Single-Grain Grinding Process

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Nanomanufacturing and Metrology 2020年第4期3卷 299-306页

作者： Xiaoguang guo Ming Li Xichun Luo Ruifeng Zhai Renke Kang Zhuji Jin dongming guo Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China Centre for Precision Manufacturing Department of DesignManufacture and Engineering ManagementUniversity of StrathclydeGlasgow G11XJUK

The smoothed-particle hydrodynamics(SPH)method was introduced to simulate the quartz glass grinding process with a single grain under micrp-nano scale.To investigate the mechanism of brittle-ductile transition,such factors as the machin-ing depth,grinding force,maximum equivalent stress,and residual stress were analyzed.The simulation results indicate that quartz glass can be machined in a ductile mode under a certain condition.In this paper,the occurrence and propaga-tion of cracks in quartz glass at different grinding depths(0.1-1μm)are observed,and the critical depth of brittle-ductile transformation is 0.36 pum.At different grinding depths,the grinding force ratio is greater than 1.When the cutting depth is 0.4 um,the crack propagation depth is about 1.2μm,which provides a basis for the prediction of subsurface damage depth.In addition,the correctness of the simulation result was verified by carrying out scratch experiments of varying cutting depth on optical quartz glass.

关键词： Quartz glass Brittle ductile transition Ultra precision grinding Smoothed particle hydrodynamics

Experimental Study on Dynamic Mechanical Properties of Sprayed Concrete-Surrounding Rock Combined Body

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Journal of Beijing Institute of Technology 2019年第2期28卷 278-285页

作者： dongming guo Pengyang Yan Longfei Fan Yingshi Zhang Xiaoye Wang School of Mechanics and Civil Engineering China University of Mining&Technology(Beijing)Beijing 100083China State Key Laboratory for Geomechanics and Deep Underground Engineering Beijing 100083China

To investigate the dynamic response problem of the double medium formed by the adherence of sprayed concrete and surrounding rock in the tunnel,a split Hopkinson pressure bar of 75 mm in diameter was adopted at the ages of 3,7 and 10 d.Experimental results showed that dynamic compressive strength and dynamic increase factors(DIF)of the combined bodies increase with the strain rate.With the growth of strain rate,the critical strain of the combined bodies first increases,then deceases.Furthermore,the combined bodies of 3 d reveal the plastic property and brittle property for 7 d and 10 d when the strain rate is over 80/s.The failure characteristic of the sprayed concrete changes from tearing strain damage to crushing damage as the growth of strain rate,and the failure characteristic of rock presents the tensile failure mode as demonstrated by the scanning electron microscope(SEM).

关键词： sprayed concrete-surrounding rock combined body dynamic compressive strength dynamic increase factors critical strain failure modes

Atomistic understanding of interfacial processing mechanism of silicon in water environment:A ReaxFF molecular dynamics simulation

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Frontiers of Mechanical Engineering 2021年第3期16卷 570-579页

作者： Song YUAN Xiaoguang guo Penghui LI Shuohua ZHANG Ming LI Zhuji JIN Renke KANG dongming guo Fumin LIU Lemin ZHANG Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China Beijing Institute of Aerospace Control Device Beijing 100854China

The interfacial wear between silicon and amorphous silica in water environment is critical in numerous applications.However,the understanding regarding the micro dynamic process is still unclear due to the limitations of apparatus.Herein,reactive force field simulations are utilized to study the interfacial process between silicon and amorphous silica in water environment,exploring the removal and damage mechanism caused by pressure,velocity,and humidity.Moreover,the reasons for high removal rate under high pressure and high velocity are elucidated from an atomic perspective.Simulation results show that the substrate is highly passivated under high humidity,and the passivation layer could alleviate the contact between the abrasive and the substrate,thus reducing the damage and wear.In addition to more Si-O-Si bridge bonds formed between the abrasive and the substrate,new removal pathways such as multibridge bonds and chain removal appear under high pressure,which cause higher removal rate and severer damage.At a higher velocity,the abrasive can induce extended tribochemical reactions and form more interfacial Si-O-Si bridge bonds,hence increasing removal rate.These results reveal the internal cause of the discrepancy in damage and removal rate under different conditions from an atomic level.

关键词： silicon ReaxFF molecular dynamics friction damage

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薄壁CFRP管端面磨削及铣削加工质量对比

复合材料学报 2024年第5期41卷 2503-2519页

作者：田俊超鲍岩康仁科张泽旭郭东明董志刚大连理工大学高性能精密制造全国重点实验室大连116024

阵列复材管是由薄壁碳纤维增强树脂基复合材料(CFRP)管在水平面内二维密排形成的蜂窝结构材料,可应用于航空航天等领域。为探索端面磨削和铣削阵列复材管的可行性,以CFRP管元胞为研究对象,考虑其薄壁特征引入切出角度为实验参数,并开展... 详细信息

阵列复材管是由薄壁碳纤维增强树脂基复合材料(CFRP)管在水平面内二维密排形成的蜂窝结构材料,可应用于航空航天等领域。为探索端面磨削和铣削阵列复材管的可行性,以CFRP管元胞为研究对象,考虑其薄壁特征引入切出角度为实验参数,并开展端面加工实验研究切出角度、刀具实际进给率、轴向切削深度和切削速度对已加工表面形貌和力的影响。结果表明:切出角度通过影响加工区域的材料支撑状态和纤维切削角影响损伤的类型及形成过程,过大或过小的切出角度均可能产生加工损伤;通过降低刀具实际进给率、轴向切削深度或提升切削速度均可一定程度上降低切削力并抑制端面磨削时小切出角度条件下的损伤,但上述措施无法抑制端面铣削损伤。端面磨削相比于端面铣削具有更大的高效低损伤加工工艺操作区间,建议优先选用。

关键词： CFRP 蜂窝铣削磨削加工损伤切削力

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人工吸收杂质诱导增透膜损伤阈值研究

光学技术 2024年第1期50卷 24-29页

作者：章汪维朱华新胡立发刘涛陈晓家郭东铭江南大学理学院江苏无锡214122 江苏省轻工光电工程技术研究中心江苏无锡214122

为研究杂质大小对增透膜激光损伤阈值(LIDT)影响,利用光刻技术在熔石英基底表面设置厚度为100nm不同直径大小的柱状金属Al“杂质吸收点”,然后在此基础上沉积增透膜。通过Comsol模拟仿真了解损伤过程,并利用532nm纳秒激光器进行阈值测试... 详细信息

为研究杂质大小对增透膜激光损伤阈值(LIDT)影响,利用光刻技术在熔石英基底表面设置厚度为100nm不同直径大小的柱状金属Al“杂质吸收点”,然后在此基础上沉积增透膜。通过Comsol模拟仿真了解损伤过程,并利用532nm纳秒激光器进行阈值测试,对实验数据与样品损伤形貌进行分析,结果表明杂质直径为50um、100um、200um、300um、400um的薄膜损伤阈值分别为18.93J/cm^(2),18.62J/cm^(2),17.11J/cm^(2),15.28J/cm^(2),13.47J/cm^(2),呈非线性下降,“杂质吸收点”吸收光能产生热量,传导于增透膜层后产生的轴向热应力超过了薄膜的拉伸强度是膜层损伤的主因。

关键词：增透膜杂质诱导薄膜损伤阈值