检索结果-南通市图书馆

Improving Mechanical Properties and Energy Absorption of Additive Manufacturing lattice structure by Struts’Node Strengthening

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2022年第6期35卷 1004-1020页

作者： Dongming Li Ruixian Qin Jianxin Xu Junxian Zhou Bingzhi Chen School of Mechanical Engineering Dalian Jiaotong UniversityDalian116028China School of Locomotive and Rolling Stock Engineering Dalian Jiaotong UniversityDalian116028China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian116028China

The lattice structure has unique performance and superior deformation behavior,which effectively stimulates the design and application of new lattice structures.The development of additive manufacturing technology makes it easy and efficient to manufacture complex lattice structures.However,it has been found that excessively high stress concentration exists at the struts’nodes during the compression of lattice structure.Therefore,three node strengthening strategies were proposed to reduce stress concentration,which were adding fillet at nodes,using circular arc transition and changing the angle of nodes.Firstly,lattice structures were manufactured by selective laser melting technique.The surface morphology of the lattice structures was observed by scanning electron microscopy.Then,the stress distribution and deformation mechanism of different lattice structures were investigated by quasi-static compression experiments and numerical simulation.Finally,the Gibson–Ashby model was adopted to predict lattice structures’modulus and strength.And the energy absorptions of different structures were compared.The results revealed that the deformation mode of the optimized structures changed from shear failure to layer-by-layer collapse.Compared with the hourglass lattice structure and gradient lattice structure,the mechanical properties of curve lattice structure were improved the most.

关键词： Node strengthening Stress concentration lattice structure Selective laser melting Deformation mode

A novel hybrid design method of lattice structure based on failure mode

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2022年第9期65卷 79-91页

作者： Chuanlei Li Junfeng Qi Panding Wang Zeang Zhao Zhe Wang Hongshuai Lei Shengyu Duan Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and structures Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Beijing Spacecrafts Beijing 100094China

Adjusting the mechanical properties of lattice structures is important for many modern application fields. In this paper, a new design method for hybrid multi-layer lattice structures was developed to improve the mechanical properties and energy absorption, by altering and suppressing the formation of the shear band. In these hybrids, all unit cells were divided into two parts:(i) diagonal unit cells and(ii) matrix unit cells. Four categories of unit cells were selected to construct the hybrid multi-layer structures. The compressive moduli, ultimate strengths, and energy absorption properties of the laser powder bed fusion(L-PBF)fabricated structures were assessed by experiments and finite element analysis(FEA). The results revealed the great impact of diagonal unit cells on the mechanical properties of the structures. Stronger diagonal unit cells than matrix unit cells led to hybrid structures with enhanced mechanical properties. Compared with a uniform body-centered cubic(BCC) lattice structure, the relative density of the lattice structure consisting of the weakest BCC matrix unit cells and strongest BFVC diagonal unit cells(coupling of BCC, FCC, and VC) exhibited an increase of 20%. The compressive modulus and ultimate strength of this structure rose by more than 200% and 90%, respectively. Two types of structures with specific properties were generated by hybrid design.The first displayed higher modulus, superior strength, and elevated specific energy absorption(SEA) but lower crash load efficiency(CLE). The second illustrated simultaneously higher SEA and elevated CLE. The present results provide a new insight for improving the load-bearing and energy absorption capacities of lattice structures.

关键词： additive manufacturing lattice structure shear deformation hybrid mechanical properties

A novel triple periodic minimal surface-like plate lattice and its data-driven optimization method for superior mechanical properties

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 217-238页

作者： Yanda WANG Yanping LIAN Zhidong WANG Chunpeng WANG Daining FANG State Key Laboratory for Turbulence and Complex Systems&Center for Applied Physics and Technology College of EngineeringPeking UniversityBeijing 100871China Institute of Advanced structure Technology Beijing Institute of TechnologyBeijing 100081China

lattice structures can be designed to achieve unique mechanical properties and have attracted increasing attention for applications in high-end industrial equipment,along with the advances in additive manufacturing(AM)technologies.In this work,a novel design of plate lattice structures described by a parametric model is proposed to enrich the design space of plate lattice structures with high connectivity suitable for AM processes.The parametric model takes the basic unit of the triple periodic minimal surface(TPMS)lattice as a skeleton and adopts a set of generation parameters to determine the plate lattice structure with different topologies,which takes the advantages of both plate lattices for superior specific mechanical properties and TPMS lattices for high connectivity,and therefore is referred to as a TPMS-like plate lattice(TLPL).Furthermore,a data-driven shape optimization method is proposed to optimize the TLPL structure for maximum mechanical properties with or without the isotropic constraints.In this method,the genetic algorithm for the optimization is utilized for global search capability,and an artificial neural network(ANN)model for individual fitness estimation is integrated for high efficiency.A set of optimized TLPLs at different relative densities are experimentally validated by the selective laser melting(SLM)fabricated samples.It is confirmed that the optimized TLPLs could achieve elastic isotropy and have superior stiffness over other isotropic lattice structures.

关键词： lattice structure triple periodic minimal surface(TPMS) plate lattice structural optimization machine learning

Binary Operations for the lattice structure in a Many-to-Many MatchingModel

在线全文

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2021年第1期9卷 207-228页

作者： Paola Belén Manasero Instituto de Matemática Aplicada San Luis Universidad Nacional de San Luis and CONICETAv.Ejército de los andes 950D5700HHW San LuisArgentina

The lattice structure of the set of stable matchings in many-to-many matching model is well known in literature.If preferences of the agents are substitutable,this result can be obtained by fixed-point methods,for that purpose an algorithm for finding a fixed-point matching is defined.Since the fixed-point set equals the set of stable matchings,the latter has a lattice structure too.In this paper,we consider a many-to-many matching market where the preferences of firms satisfy substitutability and the law of aggregate demand,and workers have responsive preferences.In this many-to-many matching market,we explicitly compute for any pair of stable matchings the least upper bound and the greatest lower bound,without using fixed-point methods.

关键词： Many-to-many matching model Binary operations lattice structure

Review of Crashworthiness Studies on Cellular structures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Automotive Innovation 2023年第3期6卷 379-403页

作者： Hongyu Liang Ying Zhao Shixian Chen Fangwu Ma Dengfeng Wang State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130022China College of Engineering and Technology Southwest UniversityChongqing 400715China Weichai Power Co. LtdWeifang 261061China

The application of lightweight structures with excellent energy absorption performance is crucial for enhancing vehicle safety and energy efficiency.Cellular structures,inspired by the characteristics observed in natural organisms,have exhibited exceptional structural utilization in terms of energy absorption compared with traditional structures.In recent years,various innovative cellular structures have been proposed to meet different engineering needs,resulting in significant performance improvements.This paper provides a comprehensive overview of novel cellular structures for energy absorption applications.In particular,it outlines the application forms and design concepts of cellular structures under typical loading conditions in vehicle collisions,including axial loading,oblique loading,bending loading,and blast loading.Cellular structures have evolved to meet the demands of complex loading conditions and diverse research methods,focusing on achieving high-performance characteristics across multiple load cases.Moreover,this review discusses manufacturing techniques and strate-gies for enhancing the manufacturing performance of cellular structures.Finally,current key challenges and future research directions for cellular structures are discussed.The aim of this study is to provide valuable guidelines for researchers and engineers in the development of next-generation lightweight cellular structures.

关键词： Honeycomb lattice structure Multi-cell tube Cellular structure filled tube Crashworthiness Multiple load cases

Enhanced energy-absorbing and sound-absorbing capability of functionally graded and helicoidal lattice structures with triply periodic minimal surfaces

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

矿物冶金与材料学报:英文版 2023年第10期30卷 1973-1985页

作者： Miao Zhao Zhendong Li Jun Wei Chua Chong Heng Lim Xinwei Li Department of Mechanical Engineering National University of SingaporeSingapore 117411Singapore Chongqing Key Laboratory of Metal Additive Manufacturing(3D Printing) Chongqing UniversityChongqing 400044China Department of Mechanical Engineering Newcastle UniversitySingapore 567739Singapore

lattice structures have drawn much attention in engineering applications due to their lightweight and multi-functional properties.In this work,a mathematical design approach for functionally graded(FG)and helicoidal lattice structures with triply periodic minimal surfaces is proposed.Four types of lattice structures including uniform,helicoidal,FG,and combined FG and helicoidal are fabricated by the additive manufacturing technology.The deformation behaviors,mechanical properties,energy absorption,and acoustic properties of lattice samples are thoroughly investigated.The load-bearing capability of helicoidal lattice samples is gradually improved in the plateau stage,leading to the plateau stress and total energy absorption improved by over 26.9%and 21.2%compared to the uniform sample,respectively.This phenomenon was attributed to the helicoidal design reduces the gap in unit cells and enhances fracture resistance.For acoustic properties,the design of helicoidal reduces the resonance frequency and improves the peak of absorption coefficient,while the FG design mainly influences the peak of absorption coefficient.Across broad range of frequency from 1000 to 6300 Hz,the maximum value of absorption coefficient is improved by18.6%-30%,and the number of points higher than 0.6 increased by 55.2%-61.7%by combining the FG and helicoidal designs.This study provides a novel strategy to simultaneously improve energy absorption and sound absorption properties by controlling the internal architecture of lattice structures.

关键词： additive manufacturing lattice structure triply periodic minimal surface energy absorption sound absorption

Challenges and strategies of lithium-rich layered oxides for Li-ion batteries

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第1期16卷 391-402页

作者： Lu Nie Shaojie Chen Wei Liu School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

Lithium-ion batteries are considered a promising energy storage technology in portable electronics and electric vehicles due to their high energy density,competitive cost,and environmental friendliness.Improving cathode materials is an effective way to meet the demand for better batteries,of which the utilization of high-voltage cathode materials is an important development trend.In recent years,lithium-rich layered oxides have gained great attention due to their desirable energy density.This review presents the relationships between lattice structure and electrochemical properties,the underlying degradation mechanisms,and corresponding modification strategies.The recent progress and strategies are then highlighted,including element doping,surface coating,morphology design,size control,etc.Finally,a concise perspective for future developments and practical applications of lithium-rich layered oxides has been provided.

关键词： lithium-ion batteries lithium-rich layered oxides lattice structure degradation mechanism element doping

Skeleton-Based Volumetric Parameterizations for lattice structures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2023年第4期135卷 687-709页

作者： Long Chen Shuxun Liang Nan Yan Xiangqian Yang Baotong Li School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai200093China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China Key Laboratory of EducationMinistry for Modern Design&Rotor-Bearing System Xi’an Jiaotong UniversityXi’an710049China

lattice structures with excellent physical properties have attracted great research interest.In this paper,a novel volume parametric modeling method based on the skeleton model is proposed for the construction of threedimensional lattice structures.The skeleton model is divided into three types of nodes.And the corresponding algorithms are utilized to construct diverse types of volume parametric nodes.The unit-cell is assembled with distinct nodes according to the geometric features.The final lattice structure is created by the periodic arrangement of unit-cells.Several different types of volume parametric lattice structures are constructed to prove the stability and applicability of the proposed method.The quality is assessed in terms of the value of the Jacobian matrix.Moreover,the volume parametric lattice structures are tested with the isogeometric analysis to verify the feasibility of integration of modeling and simulation.

关键词： lattice structure volumetric parameterization skeleton model node modeling

Fabrication of silica-based ceramic cores with internal lattice structures by stereolithography

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Foundry 2022年第5期19卷 369-379页

作者： Ke-hui Hu Hao-yuan Wang Kuan Lu Qian Feng Dao-ding Yang Jian Cao Bo Zhang Zhi-gang Lü Xing Ran State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Ten Dimensions(Guangdong)Technology Co. Ltd.Foshan 528225GuangdongChina Guizhou Anji Aviation Investment Casting Co. Ltd.Anshun 561003GuizhouChina Key Laboratory of Advanced Materials Processing Technology Ministry of EducationTsinghua UniversityBeijing 100084China

Ceramic cores are widely used in investment casting,and ideal properties of cores are essential for high-quality castings.Under the circumstances requiring thick cores,solid cores are likely to encounter deformation and cracking defects due to the accumulation of shrinkage.Therefore,with the superiority of ceramic stereolithography in producing complex ceramic parts,hollow cores with lattice structures were designed and fabricated.The dimensional accuracy and properties of the green and sintered bodies were evaluated.Results show the dimensional accuracy of sintered cores is controlled within±0.25 mm benefited from the precise green bodies.The mechanical properties are not obviously deteriorated.The bending strength reaches 11.94 MPa at room temperature and 12.87 MPa at 1,500℃ with a creep deformation of 0.345 mm.Furthermore,casting verifications prove that the hollow cores meet the requirements of investment casting.Smooth casting surfaces are obtained,at the same time,the core-removal efficiency is improved by over 3 times.

关键词： silica ceramic cores stereolithography lattice structure investment casting