From 1980’s decade,the introduction of carbon composite materials in structural applications has been consistently increased in the successive generations of civil aircraft from Single Aisle to Middle-long Range to a...From 1980’s decade,the introduction of carbon composite materials in structural applications has been consistently increased in the successive generations of civil aircraft from Single Aisle to Middle-long Range to achieve a culminant point with more than 50%in structure weight in recent commercial civil aircraft.This evolution,done through successive iterations,has been possible by combining in the same time the improvement of intrinsic composite material performances and its transformation into prepreg production technologies together with the development of new manufacturing process for material lay-up automation at composite shop-floor manufacturer of aircraft composite parts.New challenges are still coming to continuously develop materials and technologies in order to pursue the production more cost-effective composite parts.Associated to higher aircraft production rate for single aisle,new challenges may force material and aircraft designers and producers to furthermore drive new products and processes introduction and new ways of transformation within in next decade of composite aircraft designs.We propose to illustrate these trends using past and recent developments and our return of experience from Hexcel on Civil Aircraft programs.展开更多
Product design plays a decisive role in material resource consumption in manufacturing systems. So it is significant to study optimal utilization of material resources of manufacturing system from the perspective of p...Product design plays a decisive role in material resource consumption in manufacturing systems. So it is significant to study optimal utilization of material resources of manufacturing system from the perspective of product design. This paper firstly defines concept of product design, then after an analysis of design objectives the author proposes a target system of product design with three subsystems: structural system, functional system, and technical system. Finally, a product design system on Architectural Metal Structure Enterprises is developed and used in light of the great consumption of material resources in Metal Structure Enterprises. The system has got an obvious effect on improving comprehensive optimal using rate of material resources of enterprises, reducing design cycle, improving management of enterprises.展开更多
Virtual product development (VPD) is essentially based on simulation. Due tocomputational inefficiency, traditional engineering simulation software and optimization methods areinadequate to analyze optimization proble...Virtual product development (VPD) is essentially based on simulation. Due tocomputational inefficiency, traditional engineering simulation software and optimization methods areinadequate to analyze optimization problems in VPD. Optimization method based on simulationmetamodel for virtual product development is proposed to satisfy the needs of complex optimaldesigns driven by VPD. This method extends the current design of experiments (DOE) by variousmetamodeling technologies. Simulation metamodels are built to approximate detailed simulation codes,so as to provide link between optimization and simulation, or serve as a bridge for simulationsoftware integration among different domains. An example of optimal design for composite materialstructure is used to demonstrate the newly introduced method.展开更多
The processing capability is vital for the wide applications of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and functional properties.However,different ...The processing capability is vital for the wide applications of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and functional properties.However,different from usual polymers and metals,graphene solids exhibit limited deformability and processibility for precise forming.Here,we present a precise thermoplastic forming of graphene materials by polymer intercalation from graphene oxide(GO)precursor.The intercalated polymer enables the thermoplasticity of GO solids by thermally activated motion of polymer chains.We detect a critical minimum containing of intercalated polymer that can expand the interlayer spacing exceeding 1.4 nm to activate thermoplasticity,which becomes the criteria for thermal plastic forming of GO solids.By thermoplastic forming,the flat GO-composite films are forged to Gaussian curved shapes and imprinted to have surface relief patterns with size precision down to 360 nm.The plastic-formed structures maintain the structural integration with outstanding electrical(3.07×10^(5) S m^(−1))and thermal conductivity(745.65 W m^(−1) K^(−1))after removal of polymers.The thermoplastic strategy greatly extends the forming capability of GO materials and other layered materials and promises versatile structural designs for more broad applications.展开更多
Simulation and optimization are the key points of virtual product development (VPD). Traditional engineering simulation software and optimization methods are inadequate to analyze the optimization problems because of ...Simulation and optimization are the key points of virtual product development (VPD). Traditional engineering simulation software and optimization methods are inadequate to analyze the optimization problems because of its computational inefficiency. A systematic design optimization strategy by using statistical methods and mathematical optimization technologies is proposed. This method extends the design of experiments (DOE) and the simulation metamodel technologies. Metamodels are built to in place of detailed simulation codes based on effectively DOE, and then be linked to optimization routines for fast analysis, or serve as a bridge for integrating simulation software across different domains. A design optimization of composite material structure is used to demonstrate the newly introduced methodology.展开更多
MOFs are among the most popular precursors and templates for deriving various porous materials,where the derivatives can inherit a large surface area,abundant active sites for targeted functionalities and a high degre...MOFs are among the most popular precursors and templates for deriving various porous materials,where the derivatives can inherit a large surface area,abundant active sites for targeted functionalities and a high degree of porosity inherited from their parent MOFs.Those unique structural features make them promising candidates in multiple applications.More interestingly,the structure and properties of these MOF derivatives can be modulated by the choice of the parent MOFs and the design in the conversion process.In this overview,the transformation pathways from MOFs into their porous derivatives,the principles underlying these transformations,and the behavior of the MOF components in the transition process are discussed.Recently,there has been tremendous progress in preserving and enhancing the surface area,the amount of active sites and the level of porosity of the MOF-derived materials for targeted applications,from the perspectives of both customizing the parent MOFs and tailoring the transformation process.To develop the rationally designed MOF-derived materials and thus to elucidate the precursor-process-product correlations,some typical examples of the MOF derivatives applied in electrochemical energy storage and conversion,water treatment,gas sensing,and biomedicine are discussed to demonstrate the effectiveness of the key design strategies.展开更多
文摘From 1980’s decade,the introduction of carbon composite materials in structural applications has been consistently increased in the successive generations of civil aircraft from Single Aisle to Middle-long Range to achieve a culminant point with more than 50%in structure weight in recent commercial civil aircraft.This evolution,done through successive iterations,has been possible by combining in the same time the improvement of intrinsic composite material performances and its transformation into prepreg production technologies together with the development of new manufacturing process for material lay-up automation at composite shop-floor manufacturer of aircraft composite parts.New challenges are still coming to continuously develop materials and technologies in order to pursue the production more cost-effective composite parts.Associated to higher aircraft production rate for single aisle,new challenges may force material and aircraft designers and producers to furthermore drive new products and processes introduction and new ways of transformation within in next decade of composite aircraft designs.We propose to illustrate these trends using past and recent developments and our return of experience from Hexcel on Civil Aircraft programs.
基金Foundation item: Funded by China 863 R&D Program(No: 2002AA414080)
文摘Product design plays a decisive role in material resource consumption in manufacturing systems. So it is significant to study optimal utilization of material resources of manufacturing system from the perspective of product design. This paper firstly defines concept of product design, then after an analysis of design objectives the author proposes a target system of product design with three subsystems: structural system, functional system, and technical system. Finally, a product design system on Architectural Metal Structure Enterprises is developed and used in light of the great consumption of material resources in Metal Structure Enterprises. The system has got an obvious effect on improving comprehensive optimal using rate of material resources of enterprises, reducing design cycle, improving management of enterprises.
基金National Natural Science Foundation of China (No.5988950)
文摘Virtual product development (VPD) is essentially based on simulation. Due tocomputational inefficiency, traditional engineering simulation software and optimization methods areinadequate to analyze optimization problems in VPD. Optimization method based on simulationmetamodel for virtual product development is proposed to satisfy the needs of complex optimaldesigns driven by VPD. This method extends the current design of experiments (DOE) by variousmetamodeling technologies. Simulation metamodels are built to approximate detailed simulation codes,so as to provide link between optimization and simulation, or serve as a bridge for simulationsoftware integration among different domains. An example of optimal design for composite materialstructure is used to demonstrate the newly introduced method.
基金the support of the National Natural Science Foundation of China(Nos.51803177,51973191,51533008,and 51636002)National Key R&D Program of China(No.2016YFA0200200)+5 种基金the China Postdoctoral Science Foundation(No.2021M690134)Hundred Talents Program of Zhejiang University(188020*194231701/113)Key Research and Development Plan of Zhejiang Province(2018C01049)the National Postdoctoral Program for Innovative Talents(No.BX201700209)the Fundamental Research Funds for the Central Universities(2021FZZX001-17),the Natural Science Foundation of Jiangsu Province(BK20210353)the Fundamental Research Funds for the Central Universities(No.30920041106).
文摘The processing capability is vital for the wide applications of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and functional properties.However,different from usual polymers and metals,graphene solids exhibit limited deformability and processibility for precise forming.Here,we present a precise thermoplastic forming of graphene materials by polymer intercalation from graphene oxide(GO)precursor.The intercalated polymer enables the thermoplasticity of GO solids by thermally activated motion of polymer chains.We detect a critical minimum containing of intercalated polymer that can expand the interlayer spacing exceeding 1.4 nm to activate thermoplasticity,which becomes the criteria for thermal plastic forming of GO solids.By thermoplastic forming,the flat GO-composite films are forged to Gaussian curved shapes and imprinted to have surface relief patterns with size precision down to 360 nm.The plastic-formed structures maintain the structural integration with outstanding electrical(3.07×10^(5) S m^(−1))and thermal conductivity(745.65 W m^(−1) K^(−1))after removal of polymers.The thermoplastic strategy greatly extends the forming capability of GO materials and other layered materials and promises versatile structural designs for more broad applications.
文摘Simulation and optimization are the key points of virtual product development (VPD). Traditional engineering simulation software and optimization methods are inadequate to analyze the optimization problems because of its computational inefficiency. A systematic design optimization strategy by using statistical methods and mathematical optimization technologies is proposed. This method extends the design of experiments (DOE) and the simulation metamodel technologies. Metamodels are built to in place of detailed simulation codes based on effectively DOE, and then be linked to optimization routines for fast analysis, or serve as a bridge for integrating simulation software across different domains. A design optimization of composite material structure is used to demonstrate the newly introduced methodology.
基金supported by the National Natural Science Foundation of China (No.12202190)Outstanding Postdoctoral Program in Jiangsu Province (No.2022ZB233)Research Start-up Funding from Nanjing University of Aeronautics and Astronautics (No.90YAH21131)。
基金the National Research Foundation(NRF)Singapore for funding under NRF-CRP17-2017-01(R-284-000-165-281)for the research conducted at the National University of Singapore.
文摘MOFs are among the most popular precursors and templates for deriving various porous materials,where the derivatives can inherit a large surface area,abundant active sites for targeted functionalities and a high degree of porosity inherited from their parent MOFs.Those unique structural features make them promising candidates in multiple applications.More interestingly,the structure and properties of these MOF derivatives can be modulated by the choice of the parent MOFs and the design in the conversion process.In this overview,the transformation pathways from MOFs into their porous derivatives,the principles underlying these transformations,and the behavior of the MOF components in the transition process are discussed.Recently,there has been tremendous progress in preserving and enhancing the surface area,the amount of active sites and the level of porosity of the MOF-derived materials for targeted applications,from the perspectives of both customizing the parent MOFs and tailoring the transformation process.To develop the rationally designed MOF-derived materials and thus to elucidate the precursor-process-product correlations,some typical examples of the MOF derivatives applied in electrochemical energy storage and conversion,water treatment,gas sensing,and biomedicine are discussed to demonstrate the effectiveness of the key design strategies.
