检索结果-南通市图书馆

additive manufacturing of thin electrolyte layers via inkjet printing of highly-stable ceramic inks

Journal of Advanced Ceramics 2021年第2期10卷 279-290页

作者： Zhongqi Zhu Zhiyuan Gong Piao Qu Ziyong Li Sefiu Abolaji Rasaki Zhiyuan Liu Pei Wang Changyong Liu Changshi Lao Zhangwei Chen Additive Manufacturing Institute Shenzhen UniversityShenzhen518060China

Inkjet printing is a promising alternative for the fabrication of thin film components for solid oxide fuel cells(SOFCs) due to its contactless, mask free, and controllable printing process. In order to obtain satisfying electrolyte thin layer structures in anode-supported SOFCs, the preparation of suitable electrolyte ceramic inks is a key. At present, such a kind of 8 mol% Y_(2)O_(3)-stabilized ZrO_(2)(8 YSZ) electrolyte ceramic ink with long-term stability and high solid loading(> 15 wt%) seems rare for precise inkjet printing, and a number of characterization and performance aspects of the inks, such as homogeneity, viscosity, and printability, should be studied. In this study, 8 YSZ ceramic inks of varied compositions were developed for inkjet printing of SOFC ceramic electrolyte layers. The dispersing effect of two types of dispersants, i.e., polyacrylic acid ammonium(PAANH4) and polyacrylic acid(PAA), were compared. The results show that ultrasonic dispersion treatment can help effectively disperse the ceramic particles in the inks. PAANH4 has a better dispersion effect for the inks developed in this study. The inks show excellent printable performance in the actual printing process. The stability of the ink can be maintained for a storage period of over 30 days with the help of initial ultrasonic dispersion. Finally, micron-size thin 8 YSZ electrolyte films were successfully fabricated through inkjet printing and sintering, based on the as-developed high solid loading 8 YSZ inks(20 wt%). The films show fully dense and intact structural morphology and smooth interfacial bonding, offering an improved structural quality of electrolyte for enhanced SOFC performance.

关键词： inkjet printing water-based ceramic ink solid oxide fuel cell(SOFC)electrolyte 8YSZ ink stability rheological properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Collaborative optimization design of process parameter and structural topology for laser additive manufacturing

引用

Chinese Journal of Aeronautics 2023年第1期36卷 456-467页

作者： Shaoying LI Hongkai WEI Shangqin YUAN Jihong ZHU Jiang LI Weihong ZHANG State IJR Center of Aerospace Design and additive manufacturing Northwestern Polytechnical UniversityXi’an 710072China MIIT Lab of Metal additive manufacturing and Innovative Design Northwestern Polytechnical UniversityXi’an 710072China Unmanned System Research institute Northwestern Polytechnical UniversityXi’an 710072China

High-resolution laser additive manufacturing(LAM)significantly releases design free-dom,promoting the development of topology optimization(TO)and advancing structural design methods.In order to fully take advantage of voxelated forming methods and establish the quantitative relationship between the mechanical properties of printing components and multiple process factors(laser-and process-parameters),the concurrent optimization design method based on LAM should cover the process-performance relationship.This study proposes a novel artificial intelligence-facilitated TO method for LAM to concurrently design microscale material property and macroscale structural topology of 3D components by adopting heuristic and gradient-based algorithms.The process–structure–property relationship of selective laser sintering is established by the back propagation neural network,and it is integrated into the TO algorithm for providing a systematic design scheme of structural topology and process parameter.Compared with the classical optimization method,numerical examples show that this method is able to improve the mechanical performance of the macrostructure significantly.In addition,the collaborative design method is able to be widely applied for complex functional part design and optimization,as well as case studies on artificial intelligence-facilitated product evaluation.

关键词： Back propagation neural network Gradient algorithm Laser additive manufactur-ing Process–structure–property Topology optimization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Homogenization heat treatment for an additively manufactured precipitation-hardening high-entropy alloy

引用

Rare Metals 2022年第8期41卷 2853-2863页

作者： Zhi-Yuan Liu Xin-Yi Zhao Yao-Wen Wu Qiang Chen Bao-Hua Yang Pei Wang Zhang-Wei Chen Can Yang Additive Manufacturing Institute College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen518060China Sino-German College of Intelligent manufacturing Shenzhen Technology UniversityShenzhen518118China

A precipitation-hardening high-entropy alloy(HEA),(FeCoNi)_(86)Al_(7) Ti_(7),was successfully fabricated using selective laser melting(SLM).Severe segregation of Ti occurred at the boundaries of dislocation cells.Therefore,homogenization heat treatment at 1150℃for 0.5 h was performed to alleviate the microsegregation.After homogenization,almost no dislocation cells were left in the grains,and recrystallization occurred as the average grain size increased from 37 to 54μm.Compared with the initial as-built HEA,the ductility of the HEA increases significantly from 29%to 40%,and the strength decreases slightly from 710 to 606 MPa.For further aging,pre-homogenization can decrease the precipitation of ordered L2_(1) phases.Because void has a high propensity to initiate from the matrix/L2_(1) incoherent interface,pre-homogenization reduced the number of weak points,thus considerably improving the plastic deformation ability of the aged HEA by 36%.In addition,the strengthening mechanism has also been analyzed for the aged HEA.It was revealed that the coherent L1_(2)precipitate contributed the most to the increased strength.

关键词： High-entropy alloy Selective laser melting Homogenization heat treatment Strengthening mechanism

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Topology optimization of modular structures with multiple assemblies and applications to airborne shelves

引用

Chinese Journal of Aeronautics 2024年第4期37卷 321-332页

作者： Jie WANG Tong GAO Ming LI Jihong ZHU Longlong SONG Weihong ZHANG State IJR Center of Aerospace Design and additive manufacturing Northwestern Polytechnical UniversityXi’an 710072China Beijing Specialized Machinery institute Beijing 100143China

This work is devoted to the aeronautical application of topology optimization for modular structures with multiple assemblies that consist of repeated standard modules and optional reinforcements.These kinds of structures are widely used owing to their transportability,reconfigurability,low manufacturing and service costs.In this work,the design of airborne shelves with modular structures characterized by the standard module configuration is formulated for the first time as a topology optimization problem of multiple assemblies and multiple load cases subjected to the volume constraint.It is shown that the weighted compliance design of multiple assemblies is a compromising solution compared to the optimization result of each individual assembly of standard modules.Meanwhile,the performance of optimized airborne shelves with the modular structures can effectively be ameliorated with the help of reinforcements.

关键词： Topology optimization Modular structures Multiple assemblies Standard modules Airborne shelves

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Selective Laser Melting of 30CrMnSiA Steel: Laser Energy Density Dependence of Microstructural and Mechanical Properties

引用

Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 807-814页

作者： Lin-Zhi Wang Wen-Hou Wei Chongqing Key Laboratory of additive manufacturing Technology and Systems Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences

Three-dimensional parts of the 30 CrMnSiA steel were successfully fabricated using selective laser melting（SLM）. The microstructures and mechanical properties of the SLM-processed 30 CrMnSiA samples were investigated by scanning electron microscope and transmission electron microscopy. The results indicate that the microstructures of the 30 CrMnSiA samples consist mainly of lath martensite and acicular martensite. The value of the surface roughness decreases with increasing laser energy density（LED） before it reaches a minimum and then increases with further increasing LED. The relative density, microhardness and ultimate tensile strength of the SLM-processed samples initially increase and then decrease with increasing LED. By taking the relative density, surface roughness, microhardness and ultimate tensile strength into account, the optimized LED should be in the range of 46.15–51.28 J mm^（-3） for the SLM-processed30 CrMnSiA alloys. In addition, the differences in the microstructures and mechanical properties between the conventionally wrought 30 CrMnSiA sample and SLM-processed 30 CrMnSiA samples were also studied.

关键词： 30CrMnSiA Selective laser melting Laser energy density Microstructure Mechanical properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Tensile Properties and Wear Resistance of Mg Alloy Containing High Si as Implant Materials

引用

Journal of Renewable Materials 2023年第4期11卷 1977-1989页

作者： Mengqi Cong Yang Zhang Yunlong Zhang Xiao Liu Yalin Lu Xiaoping Li Key Laboratory of Advanced Materials Design and additive manufacturing of Jiangsu Province Jiangsu University of TechnologyChangzhou213001China

Magnesium alloy has been considered as one of the third-generation biomaterials for the regeneration and support of functional bone tissue.As a regeneration implant material with great potential applications,in-situ Mg_(2)Si phase reinforced Mg-6Zn cast alloy was comprehensively studied and expected to possess excellent mechanical properties via the refining and modifying of Mg_(2)Si reinforcements.The present study demonstrates that the primary and eutectic Mg_(2)Si phase can be greatly modified by the yttrium(Y)addition.The size of the primary Mg_(2)Si phases can be reduced to~20μm with an addition of 0.5 wt.%Y.This phenomenon is mainly attributed to the poisoning effect of the Y element.Moreover,wear resistance and tensile properties of the ternary alloy have also been improved by the Y addition.Mg-6Zn-4Si-0.5Y alloy exhibits optimal tensile properties and wears resistance.The ultimate tensile strength and the elongation of the alloy with 0.5 wt.%Y are 50%and 65%higher than those of the ternary alloy,respectively.Excessive Y addition(1.0 wt.%)deteriorates the tensile properties of Mg-Zn-Si alloy.The improvement of the tensile properties is mainly due to the modification of primary and eutectic Mg_(2)Si phases as well as the solid solution strengthening of the Y atoms.This study provides a certain implication for the application of Mg-Zn-Si alloys containing Y elements as regeneration implants.

关键词： Magnesium alloys Mg2Si phase microstructure regeneration mechanical properties

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Development of lunar regolith-based composite for in-situ 3D printing via high-pressure extrusion system

引用

机械工程前沿:英文版 2023年第2期18卷 253-266页

作者： Hua ZHAO Jihong ZHU Shangqin YUAN Shaoying LI Weihong ZHANG State IJR Center of Aerospace Design and additive manufacturing School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Metal High Performance additive manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’an 710072China Unmanned System Research institute Northwestern Polytechnical UniversityXi’an 710072China

To fully utilize the in-situ resources on the moon to facilitate the establishment of a lunar habitat is significant to realize the long-term residence of mankind on the moon and the deep space exploration in the future.Thus,intensive research works have been conducted to develop types of 3D printing approach to adapt to the extreme environment and utilize the lunar regolith for in-situ construction.However,the in-situ 3D printing using raw lunar regolith consumes extremely high energy and time.In this work,we proposed a cost-effective melting extrusion system for lunar regolith-based composite printing,and engineering thermoplastic powders are employed as a bonding agent for lunar regolith composite.The high-performance nylon and lunar regolith are uniformly pre-mixed in powder form with different weight fractions.The high-pressure extrusion system is helpful to enhance the interface affinity of polymer binders with lunar regolith as well as maximize the loading ratio of in-situ resources of lunar regolith.Mechanical properties such as tensile strength,elastic modulus,and Poisson’s ratio of the printed specimens were evaluated systematically.Especially,the impact performance was emphasized to improve the resistance of the meteorite impact on the moon.The maximum tensile strength and impact toughness reach 36.2 MPa and 5.15 kJ/m2,respectively.Highpressure melt extrusion for lunar regolith composite can increase the effective loading fraction up to 80 wt.% and relatively easily adapt to extreme conditions for in-situ manufacturing.

关键词： in-situ resource utilization melt extrusion molding lunar regolith-based composites mechanical properties additive manufacturing

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Stability of three-dimensional printable foam concrete as function of surfactant characteristics

引用

结构与土木工程前沿:英文版 2023年第6期17卷 935-947页

作者： Uday BODDEPALLI Indu Siva Ranjani GANDHI Biranchi PANDA Department of Civil Engineering Indian Institute of TechnologyGuwahatiAssam781039India Sustainable Resources for additive manufacturing(SReAM)Laboratory Department of Mechanical EngineeringIndian Institute of TechnologyGuwahatiAssam781039India

Extrudability is one of the most critical factors when designing three-dimensional printable foam concrete.The extrusion process likely affects the foam stability which necessitates the investigation into surfactant properties particularly for concrete mixes with high foam contents.Although many studies have been conducted on traditional foam concrete in this context,studies on three-dimensional printed foam concrete are scarce.To address this research gap,the effects of surfactant characteristics on the stability,extrudability,and buildability of three-dimensional printed foam concrete mixes with two design densities(1000 and 1300 kg/m^(3))using two different surfactants and stabilizers(synthetic-based sodium lauryl sulfate stabilized with carboxymethyl cellulose sodium salt,and natural-based hingot surfactant stabilized with xanthan gum)were investigated in this study.Fresh density tests were conducted before and after the extrusion to determine stability of the foam concrete.The results were then correlated with surfactant qualities,such as viscosity and surface tension,to understand the importance of key parameters in three-dimensional printing of foam concrete.Based on the experimental results,surfactant solu1tion with viscosity exceeding 5 m Pa·s and surface tension lower than 31 mN/m was recommended to yield stable three-dimensional printable foam concrete mixes.Nevertheless,the volume of foam in the mix significantly affected the printability characteristics.Unlike traditional foam concrete,the variation in the stabilizer concentration and density of concrete were found to have insignificant effect on the fresh-state-characteristics(slump,slump flow,and static yield stress)and air void microstructure of the stable mixes.

关键词： foam concrete 3D printable concrete stability rheology air void microstructure

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Design and applications of morphing aircraft and their structures

引用

Frontiers of Mechanical Engineering 2023年第3期18卷 1-20页

作者： Jihong ZHU Jiannan YANG Weihong ZHANG Xiaojun GU Han ZHOU State IJR Center of Aerospace Design and additive manufacturing School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi'an710072China MIIT Laboratory of Metal additive manufacturing and Innovative Design NPU-QMUL Joint Research InstituteNorthwestern Polytechnical UniversityXi'an710072China institute of Intelligence Material and Structure Unmanned System TechnologiesNorthwestern Polytechnical UniversityXi'an 710072China

Morphing aircraft can adaptively regulate their aerodynamic layout to meet the demands of varying flight conditions,improve their aerodynamic efficiency,and reduce their energy consumption.The design and fabrication of high-performance,lightweight,and intelligent morphing structures have become a hot topic in advanced aircraft design.This paper discusses morphing aircraft development history,structural characteristics,existing applications,and future prospects.First,some conventional mechanical morphing aircraft are examined with focus on their morphing modes,mechanisms,advantages,and disadvantages.Second,the novel applications of several technologies for morphing unmanned aerial vehicles,including additive manufacturing for fabricating complex morphing structures,lattice technology for reducing structural weight,and multi-mode morphing combined with flexible skins and foldable structures,are summarized and categorized.Moreover,in consideration of the further development of active morphing aircraft,the paper reviews morphing structures driven by smart material actuators,such as shape memory alloy and macro-fiber composites,and analyzes their advantages and limitations.Third,the paper discusses multiple challenges,including flexible structures,flexible skins,and control systems,in the design of future morphing aircraft.Lastly,the development and application of morphing structures in the aerospace field are discussed to provide a reference for future research and engineering applications.

关键词： morphing aircraft additive manufacturing lattice structure smart material flexible structure flexible skin

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Formation Process and Mechanical Deformation Behavior of a Novel Laser-Printed Compression-Induced Twisting-Compliant Mechanism

引用

Engineering 2022年第8期8卷 133-142页

作者： Jie Gao Dongdong Gu Chenglong Ma Donghua Dai Lixia Xi Kaijie Lin Tong Gao Jihong Zhu Yuexin Du College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China Jiangsu Engineering Laboratory for Laser additive manufacturing of High-Performance Metallic Components Nanjing University of Aeronautics and AstronauticsNanjing 210016China State IJR Center of Aerospace Design and additive manufacturing MIIT Key Laboratory of Metal High Performance Additive Manufacturing and Innovative DesignNorthwestern Polytechnical UniversityXi’an 710072China NPU-QMUL Joint Research institute of Advanced Materials and Structure Northwestern Polytechnical UniversityXi’an 710072China

A novel compression-induced twisting(CIT)-compliant mechanism was designed based on the freedom and constraint topology(FACT)method and manufactured by means of laser powder bed fusion(LPBF).The effects of LPBF printing parameters on the formability and compressive properties of the laserprinted CIT-compliant mechanism were studied.Within the range of optimized laser powers from 375 to 450 W and with the densification level of the samples maintained at above 98%,changes in the obtained relative densities of the LPBF-fabricated CIT-compliant mechanism with the applied laser powers were not apparent.Increased laser power led to the elimination of residual metallurgical pores within the inclined struts of the CIT mechanism.The highest dimensional accuracy of 0.2% and the lowest surface roughness of 20μm were achieved at a laser power of 450 W.The deformation behavior of the CIT-compliant mechanism fabricated by means of LPBF exhibited four typical stages:an elastic stage,a heterogeneous plastic deformation stage,a strength-destroying stage,and a deformation-destroying stage(or instable deformation stage).The accumulated compressive strain of the optimally printed CIT mechanism using a laser power of 450 W went up to 20% before fracturing,demonstrating a large deformation capacity.The twisting behavior and mechanical properties were investigated via a combination of finite-element simulation and experimental verification.An approximately linear relationship between the axial compressive strain and rotation angle was achieved before the strain reached 15% for the LPBF-processed CIT-compliant mechanism.

关键词： Laser 3D printing Laser powder bed fusion Compression-induced twisting-compliant mechanism Compression-torsion property Mechanical properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：