Owning various crystal structures and high theoretical capacity,metal tellurides are emerging as promising electrode materials for high-performance metal-ion batteries(MBs).Since metal telluride-based MBs are quite ne...Owning various crystal structures and high theoretical capacity,metal tellurides are emerging as promising electrode materials for high-performance metal-ion batteries(MBs).Since metal telluride-based MBs are quite new,fundamental issues raise regarding the energy storage mechanism and other aspects affecting electrochemical performance.Severe volume expansion,low intrinsic conductivity and slow ion diffusion kinetics jeopardize the performance of metal tellurides,so that rational design and engineering are crucial to circumvent these disadvantages.Herein,this review provides an in-depth discussion of recent investigations and progresses of metal tellurides,beginning with a critical discussion on the energy storage mechanisms of metal tellurides in various MBs.In the following,recent design and engineering strategies of metal tellurides,including morphology engineering,compositing,defect engineering and heterostructure construction,for high-performance MBs are summarized.The primary focus is to present a comprehensive understanding of the structural evolution based on the mechanism and corresponding effects of dimension control,composition,electron configuration and structural complexity on the electrochemical performance.In closing,outlooks and prospects for future development of metal tellurides are proposed.This work also highlights the promising directions of design and engineering strategies of metal tellurides with high performance and low cost.展开更多
The additive design (AD) and additive manufacturing (AM) of jet engine parts will revolutionize the traditional aerospace industry. The unique characteristics of AM, such as gradient materials and micro-structures...The additive design (AD) and additive manufacturing (AM) of jet engine parts will revolutionize the traditional aerospace industry. The unique characteristics of AM, such as gradient materials and micro-structures, have opened up a new direction in jet engine design and manufacturing. Engineers have been liberated from many constraints associated with traditional methodologies and technologies. One of the most significant features of the AM process is that it can ensure the consistency of parts because it starts from point(s), continues to line(s) and layer(s), and ends with the competed part. Collaboration between design and manufacturing is the key to success in fields including aerodynamics, thermodynamics, structural integration, heat transfer, material development, and machining. Engineers must change the way they design a part, as they shift from the traditional method of "subtracting material" to the new method of "adding material" in order to manufacture a part. AD is not the same as designing for AM, A new method and new tools are required to assist with this new way of designing and manufacturing. This paper discusses in detail what is required in AD and AM, and how current problems can be solved.展开更多
New materials are fundamental to the growth,security,and quality of life of human being sand open doors to technologies in civil,chemical,nuclear,aeronautical,mechanical,biomedical,and electrical engineering.Creative ...New materials are fundamental to the growth,security,and quality of life of human being sand open doors to technologies in civil,chemical,nuclear,aeronautical,mechanical,biomedical,and electrical engineering.Creative companies use multiple materials in the development of their activities,such as solid stone,fiber glass,concrete,and glass reinforced concrete,for example.Based on bibliographic research,the article examines the synergy between materials science&engineering and creative economy.The main argument indicates that this synergy creates solutions and functionalities that add value to existing products and allow the development of new products with competitive advantages.It may also contribute to the preservation of cultural values and promote sustainability.展开更多
In this paper,the Web-based integration methodology and framework have been developed to facilitate collabora- tive and concurrent engineering design in distributed manufacturing environments.The distributed concurren...In this paper,the Web-based integration methodology and framework have been developed to facilitate collabora- tive and concurrent engineering design in distributed manufacturing environments.The distributed concurrent engineering and co- design are discussed as key components in the mechanism.The related integration system is presented,which includes four function- al modules:co-design,Web-based visualization,manufacturing analysis and look-up service.It can be used for a design team geo- graphically distributed to organize a collaborative and concurrent engineering design effectively.In particular,the collaborative mechanism incorporated with Java-based and Internet-enabled technologies can generate extended strategies for design and planning. Thus,the proposed integration architecture enables the system to be generic,open and scalable.Finally,for the trend of global manufacturing,a case study of Internet-enabled collaborative optimization is introduced and a discussion on teamwork capability is made.展开更多
Eutectic high-entropy alloys(EHEAs),combining the advantages of both eutectic alloys and high-entropy alloys(HEAs),possess good castability and superior comprehensive mechanical properties which are regarded as a revo...Eutectic high-entropy alloys(EHEAs),combining the advantages of both eutectic alloys and high-entropy alloys(HEAs),possess good castability and superior comprehensive mechanical properties which are regarded as a revolutionary material system.In this paper,a current study of EHEAs is captured comprehensively for the first time,including basic theory,microstructure and deformation behavior,and alloy design.An in-depth analysis of the formation of different microstructures of EHEAs and their mechanical properties is presented,and four methods of designing EHEAs are summarized.Due to their unique characteristics,EHEAs show great potential in materials processing engineering.Here we give a comprehensive summary of their applications in welding,surface engineering,and additive manufacturing for the first time.Among them,EHEAs in welding are divided into three sections based on different welding techniques:fusion-based welding,solid-state welding,and diffusion reaction-based welding;EHEAs in surface engineering are separated into two parts:surface modification of bulk EHEAs and EHEA coatings;EHEAs in additive manufacturing are elaborated in two parts:laser powder bed fusion(LPBF)and laser direct energy deposition(LDED).Finally,a summary is given and a future outlook is prospected.展开更多
Among a promising photovoltaic technology for solar energy conversion,organic solar cells(OSCs)have been paid much attention,of which the power conversion efficiencies(PCEs)have rapidly surpassed over 20%,approaching t...Among a promising photovoltaic technology for solar energy conversion,organic solar cells(OSCs)have been paid much attention,of which the power conversion efficiencies(PCEs)have rapidly surpassed over 20%,approaching the threshold for potential applications.However,the device stability of OSCs including storage stability,photostability and thermal stability,remains to be an enormous challenge when faced with practical applications.The major causes of device instability are rooted in the poor inherent properties of light-harvesting materials,metastable mor-phology,interfacial reactions and highly sensitive to external stresses.To get rid of theseflaws,a comprehensive review is provided about recent strategies and meth-ods for improving the device stability from active layers,interfacial layers,device engineering and encapsulation techniques for high-performance OSC devices.In the end,prospectives for the next stage development of high-performance devices with satisfactory long-term stability are afforded for the solar community.展开更多
In this paper, the operating conditions, technical requirements, performance characteristics, design ideas, application experiences and development trends of aerospace engine bearings, including material technology, i...In this paper, the operating conditions, technical requirements, performance characteristics, design ideas, application experiences and development trends of aerospace engine bearings, including material technology, integration design and reliability, are reviewed. The development history of aerospace engine bearing is recalled briefly at first. Then today's material technologies and the high bearing performances of the bearings obtained through the new materials are introduced, which play important roils in the aeroengine bearing developments. The integration design ideas and practices are explained to indicate its significant advantages and importance to the aerospace engine bearings. And the reliability of the shaft-bearing system is pointed out and treated as the key requirement with goals for both engine and bearing. Finally, as it is believed that the correct design comes from practice, the pre-qualification rig testing conducted by FAG Aerospace GmbH & Co. KG is briefly illustrated as an example. All these lead to the development trends of aerospace engine bearings from different aspects.展开更多
Metal additive manufacturing(MAM)technology has experienced rapid development in recent years.As both equipment and materials progress towards increased maturity and commercialization,material metallurgy technology ba...Metal additive manufacturing(MAM)technology has experienced rapid development in recent years.As both equipment and materials progress towards increased maturity and commercialization,material metallurgy technology based on high energy sources has become a key factor influencing the future development of MAM.The calculation of phase diagrams(CALPHAD)is an essential method and tool for constructing multi-component phase diagrams by employing experimental phase diagrams and Gibbs free energy models of simple systems.By combining with the element mobility data and non-equilibrium phase transition model,it has been widely used in the analysis of traditional metal materials.The development of CALPHAD application technology for MAM is focused on the compositional design of printable materials,the reduction of metallurgical imperfections,and the control of microstructural attributes.This endeavor carries considerable theoretical and practical significance.This paper summarizes the important achievements of CALPHAD in additive manufacturing(AM)technology in recent years,including material design,process parameter optimization,microstructure evolution simulation,and properties prediction.Finally,the limitations of applying CALPHAD technology to MAM technology are discussed,along with prospective research directions.展开更多
Metal-halide hybrid perovskite materials are excellent candidates for solar cells and photoelectric devices.In recent years,machine learning(ML)techniques have developed rapidly in many fields and provided ideas for m...Metal-halide hybrid perovskite materials are excellent candidates for solar cells and photoelectric devices.In recent years,machine learning(ML)techniques have developed rapidly in many fields and provided ideas for material discovery and design.ML can be applied to discover new materials quickly and effectively,with significant savings in resources and time compared with traditional experiments and density functional theory(DFT)calculations.In this review,we present the application of ML in per-ovskites and briefly review the recent works in the field of ML-assisted perovskite design.Firstly,the advantages of perovskites in solar cells and the merits of ML applied to perovskites are discussed.Secondly,the workflow of ML in perovskite design and some basic ML algorithms are introduced.Thirdly,the applications of ML in predicting various properties of perovskite materials and devices are reviewed.Finally,we propose some prospects for the future development of this field.The rapid devel-opment of ML technology will largely promote the process of materials science,and ML will become an increasingly popular method for predicting the target properties of materials and devices.展开更多
Rolling stock manufacturers are finding structural solutions to reduce power required by the vehicles,and the lightweight design of the car body represents a possible solution.Optimization processes and innovative mat...Rolling stock manufacturers are finding structural solutions to reduce power required by the vehicles,and the lightweight design of the car body represents a possible solution.Optimization processes and innovative materials can be combined in order to achieve this goal.In this framework,we propose the redesign and optimization process of the car body roof for a light rail vehicle,introducing a sandwich structure.Bonded joint was used as a fastening system.The project was carried out on a single car of a modern tram platform.This preliminary numerical work was developed in two main steps:redesign of the car body structure and optimization of the innovated system.Objective of the process was the mass reduction of the whole metallic structure,while the constraint condition was imposed on the first frequency of vibration of the system.The effect of introducing a sandwich panel within the roof assembly was evaluated,focusing on the mechanical and dynamic performances of the whole car body.A mass saving of 63%on the optimized components was achieved,corresponding to a 7.6%if compared to the complete car body shell.In addition,a positive increasing of 17.7%on the first frequency of vibration was observed.Encouraging results have been achieved in terms of weight reduction and mechanical behaviour of the innovated car body.展开更多
In the last decade, parametric and generative design techniques become quite popular for form-finding strategies or for pushing automation in design processes. Nevertheless, these techniques could be applied in engine...In the last decade, parametric and generative design techniques become quite popular for form-finding strategies or for pushing automation in design processes. Nevertheless, these techniques could be applied in engineering processes as well in order to improve the effectiveness and the efficiency of manufacturing processes in BI (building industry). Focusing on the case study of GLT (glued-laminated timber), this paper shows the procedure of programming a parametric algorithm adopted by authors that pursues two specific design intents: reducing the usage of unneeded high-quality raw material and improving the efficiency of production processes by producing DF (digital fabrication) contents for standard production systems of GLT. According to different European and international standards, thanks to FEM (finite element model) simulations and curvature analysis, the algorithm allows saving at least 33% of high-quality raw material and, according to early first surveys on a standard production system, 30% of operation time among product engineering-processes.展开更多
Artificial intelligent aided design and manufacturing have been recognized as one kind of robust data-driven and data-intensive technologies in the integrated computational material engi-neering(ICME)era.Motivated by ...Artificial intelligent aided design and manufacturing have been recognized as one kind of robust data-driven and data-intensive technologies in the integrated computational material engi-neering(ICME)era.Motivated by the dramatical developments of the services of China Railway High-speed series for more than a decade,it is essential to reveal the foundations of lifecycle man-agement of those trains under environmental conditions.Here,the smart design and manufacturing of welded Q350 steel frames of CR200J series are introduced,presenting the capability and opportu-nity of ICME in weight reduction and lifecycle management at a cost-effective approach.In order to address the required fatigue life time enduring more than 9×10^(6)km,the response of optimized frames to the static and the dynamic loads are comprehensively investigated.It is highlighted that the maximum residual stress of the optimized welded frame is reduced to 69 MPa from 477 MPa of previous existing one.Based on the measured stress and acceleration from the railways,the fatigue life of modified frame under various loading modes could fulfil the requirements of the lifecycle man-agement.Moreover,our recent developed intelligent quality control strategy of welding process mediated by machine learning is also introduced,envisioning its application in the intelligent weld-ing.展开更多
This research explores the prospect of fabricating a face-centered cubic(fcc) Ni-base alloy cladding(Inconel 690) on an fcc Fe-base alloy(316 L stainless-steel) having improved mechanical properties and reduced sensit...This research explores the prospect of fabricating a face-centered cubic(fcc) Ni-base alloy cladding(Inconel 690) on an fcc Fe-base alloy(316 L stainless-steel) having improved mechanical properties and reduced sensitivity to corrosion through grain boundary and microstructure engineering concepts enabled by additive manufacturing(AM) utilizing electron-beam powder bed fusion(EPBF). The unique solidification and associated constitutional supercooling phenomena characteristic of EPBF promotes[100] textured and extended columnar grains having lower energy grain boundaries as opposed to random, high-angle grain boundaries, but no coherent {111} twin boundaries characteristic of conventional thermo-mechanically processed fcc metals and alloys, including Inconel 690 and 316 L stainless-steel.In addition to [100] textured grains, columnar grains were produced by EPBF fabrication of Inconel 690 claddings on 316 L stainless-steel substrates. Also, irregular 2–3 μm diameter, low energy subgrains were formed along with dislocation densities varying from 108 to 109 cm^2, and a homogeneous distribution of Cr_(23)C_6 precipitates. Precipitates were formed within the grains(with ~3 μm interparticle spacing),but not in the subgrain or columnar grain boundaries. These inclusive, hierarchical microstructures produced a tensile yield strength of 0.527 GPa, elongation of 21%, and Vickers microindentation hardness of 2.33 GPa for the Inconel 690 cladding in contrast to a tensile yield strength of 0.327 GPa, elongation of 53%, and Vickers microindentation hardness of 1.78 GPa, respectively for the wrought 316 L stainlesssteel substrate. Aging of both the Inconel 690 cladding and the 316 L stainless-steel substrate at 685?C for50 h precipitated Cr_(23)C_6 carbides in the Inconel 690 columnar grain boundaries, but not in the low-angle(and low energy) subgrain boundaries. In contrast, Cr_(23)C_6 carbides precipitated in the 316 L stainless-steel grain boundaries, but not in the low energy coherent {111} twin boundaries. Consequently, the Inconel690 subgrain boundaries essentially serve as surrogates for coherent twin boundaries with regard to avoiding carbide precipitation and corrosion sensitization.展开更多
This paper is standing on the recent viewpoint originated from relevant industrial practices that well or-ganized tracing, representing and feedback(TRF) mechanism of material-flow information is crucial for system ut...This paper is standing on the recent viewpoint originated from relevant industrial practices that well or-ganized tracing, representing and feedback(TRF) mechanism of material-flow information is crucial for system utility and usability of manufacturing execution systems(MES), essentially, for activities on the side of multi-level decision making and optimization mainly in the planning and scheduling. In this paper, we investigate a key issue emphasized on a route of multi-level information evolution on the side of large-scale feedback, where material-flow states could evolve from the measuring data(local states) to networked event-type information cells(global states) and consequently to the key performance indicators(KPI) type information(gross states). Importantly, with adapta-bilities to frequent structural dynamics residing in running material flows, this evolving route should be modeled as a suit of sophisticated mechanism for large-scale dynamic states tracking and representing so as to upgrade accu-racy and usability of the feedback information in MES. To clarify inherent complexities of this evolving route, the investigated issue is demonstrated from extended process systems engineering(PSE) point of view, and the TRF principles of the multi-level feedback information(states) are highlighted under the multi-scale methodology. As the main contribution, a novel mechanism called TRF modeling mechanism is introduced.展开更多
In this paper the importance of DFM/CAPP/CAM system in Concurrent Engineering (CE) is discussed. Based on the analyses of the character of concurrent product design and manufacturing process design, the workflow of ...In this paper the importance of DFM/CAPP/CAM system in Concurrent Engineering (CE) is discussed. Based on the analyses of the character of concurrent product design and manufacturing process design, the workflow of DFM/CAPP/CAM system in CE is given. DFM/CAPP/CAM theories, methods and functions are investigated in a delicate and all round way, and are implemented in the developed DFM/CAPP/CAM system.展开更多
基金supported by the International Collaboration Program of Jilin Provincial Department of Science and Technology,China(20230402051GH)the National Natural Science Foundation of China(51932003,51902050)+2 种基金the Open Project Program of Key Laboratory of Preparation and Application of Environmental friendly Materials(Jilin Normal University)of Ministry of China(2021006)the Fundamental Research Funds for the Central Universities JLU“Double-First Class”Discipline for Materials Science&Engineering。
文摘Owning various crystal structures and high theoretical capacity,metal tellurides are emerging as promising electrode materials for high-performance metal-ion batteries(MBs).Since metal telluride-based MBs are quite new,fundamental issues raise regarding the energy storage mechanism and other aspects affecting electrochemical performance.Severe volume expansion,low intrinsic conductivity and slow ion diffusion kinetics jeopardize the performance of metal tellurides,so that rational design and engineering are crucial to circumvent these disadvantages.Herein,this review provides an in-depth discussion of recent investigations and progresses of metal tellurides,beginning with a critical discussion on the energy storage mechanisms of metal tellurides in various MBs.In the following,recent design and engineering strategies of metal tellurides,including morphology engineering,compositing,defect engineering and heterostructure construction,for high-performance MBs are summarized.The primary focus is to present a comprehensive understanding of the structural evolution based on the mechanism and corresponding effects of dimension control,composition,electron configuration and structural complexity on the electrochemical performance.In closing,outlooks and prospects for future development of metal tellurides are proposed.This work also highlights the promising directions of design and engineering strategies of metal tellurides with high performance and low cost.
文摘The additive design (AD) and additive manufacturing (AM) of jet engine parts will revolutionize the traditional aerospace industry. The unique characteristics of AM, such as gradient materials and micro-structures, have opened up a new direction in jet engine design and manufacturing. Engineers have been liberated from many constraints associated with traditional methodologies and technologies. One of the most significant features of the AM process is that it can ensure the consistency of parts because it starts from point(s), continues to line(s) and layer(s), and ends with the competed part. Collaboration between design and manufacturing is the key to success in fields including aerodynamics, thermodynamics, structural integration, heat transfer, material development, and machining. Engineers must change the way they design a part, as they shift from the traditional method of "subtracting material" to the new method of "adding material" in order to manufacture a part. AD is not the same as designing for AM, A new method and new tools are required to assist with this new way of designing and manufacturing. This paper discusses in detail what is required in AD and AM, and how current problems can be solved.
文摘New materials are fundamental to the growth,security,and quality of life of human being sand open doors to technologies in civil,chemical,nuclear,aeronautical,mechanical,biomedical,and electrical engineering.Creative companies use multiple materials in the development of their activities,such as solid stone,fiber glass,concrete,and glass reinforced concrete,for example.Based on bibliographic research,the article examines the synergy between materials science&engineering and creative economy.The main argument indicates that this synergy creates solutions and functionalities that add value to existing products and allow the development of new products with competitive advantages.It may also contribute to the preservation of cultural values and promote sustainability.
文摘In this paper,the Web-based integration methodology and framework have been developed to facilitate collabora- tive and concurrent engineering design in distributed manufacturing environments.The distributed concurrent engineering and co- design are discussed as key components in the mechanism.The related integration system is presented,which includes four function- al modules:co-design,Web-based visualization,manufacturing analysis and look-up service.It can be used for a design team geo- graphically distributed to organize a collaborative and concurrent engineering design effectively.In particular,the collaborative mechanism incorporated with Java-based and Internet-enabled technologies can generate extended strategies for design and planning. Thus,the proposed integration architecture enables the system to be generic,open and scalable.Finally,for the trend of global manufacturing,a case study of Internet-enabled collaborative optimization is introduced and a discussion on teamwork capability is made.
基金supported by the National Natural Science Foun-dation of China(Grant Nos.52205348 and 52275321)the Natural Science Foundation of Shandong Province(Grant Nos.ZR2023JQ021 and ZR2022QE087).
文摘Eutectic high-entropy alloys(EHEAs),combining the advantages of both eutectic alloys and high-entropy alloys(HEAs),possess good castability and superior comprehensive mechanical properties which are regarded as a revolutionary material system.In this paper,a current study of EHEAs is captured comprehensively for the first time,including basic theory,microstructure and deformation behavior,and alloy design.An in-depth analysis of the formation of different microstructures of EHEAs and their mechanical properties is presented,and four methods of designing EHEAs are summarized.Due to their unique characteristics,EHEAs show great potential in materials processing engineering.Here we give a comprehensive summary of their applications in welding,surface engineering,and additive manufacturing for the first time.Among them,EHEAs in welding are divided into three sections based on different welding techniques:fusion-based welding,solid-state welding,and diffusion reaction-based welding;EHEAs in surface engineering are separated into two parts:surface modification of bulk EHEAs and EHEA coatings;EHEAs in additive manufacturing are elaborated in two parts:laser powder bed fusion(LPBF)and laser direct energy deposition(LDED).Finally,a summary is given and a future outlook is prospected.
基金Shenzhen Fundamental Research Program,Grant/Award Number:JCYJ20210324120010028National Natural Science Foundation of China,Grant/Award Number:22225504Guangdong Provincial Key Laboratory of Catalysis,Grant/Award Number:2020B121201002。
文摘Among a promising photovoltaic technology for solar energy conversion,organic solar cells(OSCs)have been paid much attention,of which the power conversion efficiencies(PCEs)have rapidly surpassed over 20%,approaching the threshold for potential applications.However,the device stability of OSCs including storage stability,photostability and thermal stability,remains to be an enormous challenge when faced with practical applications.The major causes of device instability are rooted in the poor inherent properties of light-harvesting materials,metastable mor-phology,interfacial reactions and highly sensitive to external stresses.To get rid of theseflaws,a comprehensive review is provided about recent strategies and meth-ods for improving the device stability from active layers,interfacial layers,device engineering and encapsulation techniques for high-performance OSC devices.In the end,prospectives for the next stage development of high-performance devices with satisfactory long-term stability are afforded for the solar community.
文摘In this paper, the operating conditions, technical requirements, performance characteristics, design ideas, application experiences and development trends of aerospace engine bearings, including material technology, integration design and reliability, are reviewed. The development history of aerospace engine bearing is recalled briefly at first. Then today's material technologies and the high bearing performances of the bearings obtained through the new materials are introduced, which play important roils in the aeroengine bearing developments. The integration design ideas and practices are explained to indicate its significant advantages and importance to the aerospace engine bearings. And the reliability of the shaft-bearing system is pointed out and treated as the key requirement with goals for both engine and bearing. Finally, as it is believed that the correct design comes from practice, the pre-qualification rig testing conducted by FAG Aerospace GmbH & Co. KG is briefly illustrated as an example. All these lead to the development trends of aerospace engine bearings from different aspects.
基金supported by the National Key Research and Development Program of China(No.2021YFB3702500)。
文摘Metal additive manufacturing(MAM)technology has experienced rapid development in recent years.As both equipment and materials progress towards increased maturity and commercialization,material metallurgy technology based on high energy sources has become a key factor influencing the future development of MAM.The calculation of phase diagrams(CALPHAD)is an essential method and tool for constructing multi-component phase diagrams by employing experimental phase diagrams and Gibbs free energy models of simple systems.By combining with the element mobility data and non-equilibrium phase transition model,it has been widely used in the analysis of traditional metal materials.The development of CALPHAD application technology for MAM is focused on the compositional design of printable materials,the reduction of metallurgical imperfections,and the control of microstructural attributes.This endeavor carries considerable theoretical and practical significance.This paper summarizes the important achievements of CALPHAD in additive manufacturing(AM)technology in recent years,including material design,process parameter optimization,microstructure evolution simulation,and properties prediction.Finally,the limitations of applying CALPHAD technology to MAM technology are discussed,along with prospective research directions.
基金funded by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDA17040506)the National Natural Science Foundation of China(62005148/12004235)+2 种基金The Open Competition Mechanism to Select The Best Candidates Project in Jinzhong Science and Technology Bureau (J202101)the DNL Cooperation Fund CAS(DNL180311)the 111 Project (B14041)
文摘Metal-halide hybrid perovskite materials are excellent candidates for solar cells and photoelectric devices.In recent years,machine learning(ML)techniques have developed rapidly in many fields and provided ideas for material discovery and design.ML can be applied to discover new materials quickly and effectively,with significant savings in resources and time compared with traditional experiments and density functional theory(DFT)calculations.In this review,we present the application of ML in per-ovskites and briefly review the recent works in the field of ML-assisted perovskite design.Firstly,the advantages of perovskites in solar cells and the merits of ML applied to perovskites are discussed.Secondly,the workflow of ML in perovskite design and some basic ML algorithms are introduced.Thirdly,the applications of ML in predicting various properties of perovskite materials and devices are reviewed.Finally,we propose some prospects for the future development of this field.The rapid devel-opment of ML technology will largely promote the process of materials science,and ML will become an increasingly popular method for predicting the target properties of materials and devices.
文摘Rolling stock manufacturers are finding structural solutions to reduce power required by the vehicles,and the lightweight design of the car body represents a possible solution.Optimization processes and innovative materials can be combined in order to achieve this goal.In this framework,we propose the redesign and optimization process of the car body roof for a light rail vehicle,introducing a sandwich structure.Bonded joint was used as a fastening system.The project was carried out on a single car of a modern tram platform.This preliminary numerical work was developed in two main steps:redesign of the car body structure and optimization of the innovated system.Objective of the process was the mass reduction of the whole metallic structure,while the constraint condition was imposed on the first frequency of vibration of the system.The effect of introducing a sandwich panel within the roof assembly was evaluated,focusing on the mechanical and dynamic performances of the whole car body.A mass saving of 63%on the optimized components was achieved,corresponding to a 7.6%if compared to the complete car body shell.In addition,a positive increasing of 17.7%on the first frequency of vibration was observed.Encouraging results have been achieved in terms of weight reduction and mechanical behaviour of the innovated car body.
文摘In the last decade, parametric and generative design techniques become quite popular for form-finding strategies or for pushing automation in design processes. Nevertheless, these techniques could be applied in engineering processes as well in order to improve the effectiveness and the efficiency of manufacturing processes in BI (building industry). Focusing on the case study of GLT (glued-laminated timber), this paper shows the procedure of programming a parametric algorithm adopted by authors that pursues two specific design intents: reducing the usage of unneeded high-quality raw material and improving the efficiency of production processes by producing DF (digital fabrication) contents for standard production systems of GLT. According to different European and international standards, thanks to FEM (finite element model) simulations and curvature analysis, the algorithm allows saving at least 33% of high-quality raw material and, according to early first surveys on a standard production system, 30% of operation time among product engineering-processes.
基金supported by the National Basic Scientific Research Project of China (No.JCKY2020607B003)CRRC (No.202CDA001)
文摘Artificial intelligent aided design and manufacturing have been recognized as one kind of robust data-driven and data-intensive technologies in the integrated computational material engi-neering(ICME)era.Motivated by the dramatical developments of the services of China Railway High-speed series for more than a decade,it is essential to reveal the foundations of lifecycle man-agement of those trains under environmental conditions.Here,the smart design and manufacturing of welded Q350 steel frames of CR200J series are introduced,presenting the capability and opportu-nity of ICME in weight reduction and lifecycle management at a cost-effective approach.In order to address the required fatigue life time enduring more than 9×10^(6)km,the response of optimized frames to the static and the dynamic loads are comprehensively investigated.It is highlighted that the maximum residual stress of the optimized welded frame is reduced to 69 MPa from 477 MPa of previous existing one.Based on the measured stress and acceleration from the railways,the fatigue life of modified frame under various loading modes could fulfil the requirements of the lifecycle man-agement.Moreover,our recent developed intelligent quality control strategy of welding process mediated by machine learning is also introduced,envisioning its application in the intelligent weld-ing.
基金Support for this project was provided by US Department of Energy grant DE-SC0011826
文摘This research explores the prospect of fabricating a face-centered cubic(fcc) Ni-base alloy cladding(Inconel 690) on an fcc Fe-base alloy(316 L stainless-steel) having improved mechanical properties and reduced sensitivity to corrosion through grain boundary and microstructure engineering concepts enabled by additive manufacturing(AM) utilizing electron-beam powder bed fusion(EPBF). The unique solidification and associated constitutional supercooling phenomena characteristic of EPBF promotes[100] textured and extended columnar grains having lower energy grain boundaries as opposed to random, high-angle grain boundaries, but no coherent {111} twin boundaries characteristic of conventional thermo-mechanically processed fcc metals and alloys, including Inconel 690 and 316 L stainless-steel.In addition to [100] textured grains, columnar grains were produced by EPBF fabrication of Inconel 690 claddings on 316 L stainless-steel substrates. Also, irregular 2–3 μm diameter, low energy subgrains were formed along with dislocation densities varying from 108 to 109 cm^2, and a homogeneous distribution of Cr_(23)C_6 precipitates. Precipitates were formed within the grains(with ~3 μm interparticle spacing),but not in the subgrain or columnar grain boundaries. These inclusive, hierarchical microstructures produced a tensile yield strength of 0.527 GPa, elongation of 21%, and Vickers microindentation hardness of 2.33 GPa for the Inconel 690 cladding in contrast to a tensile yield strength of 0.327 GPa, elongation of 53%, and Vickers microindentation hardness of 1.78 GPa, respectively for the wrought 316 L stainlesssteel substrate. Aging of both the Inconel 690 cladding and the 316 L stainless-steel substrate at 685?C for50 h precipitated Cr_(23)C_6 carbides in the Inconel 690 columnar grain boundaries, but not in the low-angle(and low energy) subgrain boundaries. In contrast, Cr_(23)C_6 carbides precipitated in the 316 L stainless-steel grain boundaries, but not in the low energy coherent {111} twin boundaries. Consequently, the Inconel690 subgrain boundaries essentially serve as surrogates for coherent twin boundaries with regard to avoiding carbide precipitation and corrosion sensitization.
基金Supported by the National Basic Research Program of China(2012CB720500)the National High Technology Research and Development Program of China(2012AA041102)
文摘This paper is standing on the recent viewpoint originated from relevant industrial practices that well or-ganized tracing, representing and feedback(TRF) mechanism of material-flow information is crucial for system utility and usability of manufacturing execution systems(MES), essentially, for activities on the side of multi-level decision making and optimization mainly in the planning and scheduling. In this paper, we investigate a key issue emphasized on a route of multi-level information evolution on the side of large-scale feedback, where material-flow states could evolve from the measuring data(local states) to networked event-type information cells(global states) and consequently to the key performance indicators(KPI) type information(gross states). Importantly, with adapta-bilities to frequent structural dynamics residing in running material flows, this evolving route should be modeled as a suit of sophisticated mechanism for large-scale dynamic states tracking and representing so as to upgrade accu-racy and usability of the feedback information in MES. To clarify inherent complexities of this evolving route, the investigated issue is demonstrated from extended process systems engineering(PSE) point of view, and the TRF principles of the multi-level feedback information(states) are highlighted under the multi-scale methodology. As the main contribution, a novel mechanism called TRF modeling mechanism is introduced.
文摘In this paper the importance of DFM/CAPP/CAM system in Concurrent Engineering (CE) is discussed. Based on the analyses of the character of concurrent product design and manufacturing process design, the workflow of DFM/CAPP/CAM system in CE is given. DFM/CAPP/CAM theories, methods and functions are investigated in a delicate and all round way, and are implemented in the developed DFM/CAPP/CAM system.