In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and pro...In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel.展开更多
With the increase in research on AI(Artificial Intelligence),the importance of DL(Deep Learning)in various fields,such as materials,biotechnology,genomes,and new drugs,is increasing significantly,thereby increasing th...With the increase in research on AI(Artificial Intelligence),the importance of DL(Deep Learning)in various fields,such as materials,biotechnology,genomes,and new drugs,is increasing significantly,thereby increasing the number of deep-learning framework users.However,to design a deep neural network,a considerable understanding of the framework is required.To solve this problem,a GUI(Graphical User Interface)-based DNN(Deep Neural Network)design tool is being actively researched and developed.The GUI-based DNN design tool can design DNNs quickly and easily.However,the existing GUI-based DNN design tool has certain limitations such as poor usability,framework dependency,and difficulty encountered in changing GUI components.In this study,a deep learning algorithm that solves the problem of poor usability was developed using a template to increase the accessibility for users.Moreover,the proposed tool was developed to save and share only the necessary parts for quick operation.To solve the framework dependency,we applied ONNX(Open Neural Network Exchange),which is an exchange standard for neural networks,and configured it such that DNNs designed with the existing deep-learning framework can be imported.Finally,to address the difficulty encountered in changing GUI components,we defined and developed the JSON format to quickly respond to version updates.The developed DL neural network designer was validated by running it with KISTI’s supercomputer-based AI Studio.展开更多
Collaboration in large projects is a major challenge for contemporary architectural practice and this paper presents a notation for describing and analyzing how these collaborations can take place.Based on an extensiv...Collaboration in large projects is a major challenge for contemporary architectural practice and this paper presents a notation for describing and analyzing how these collaborations can take place.Based on an extensive literature review some opportunities were found for the development of a notation that combined three particular aspects:network diagrams,Euler diagrams and a model from architectural design.An exploratory case study was conducted based on the collaboration during a complex architectural project,which combined three approaches:document analysis,semi-structured interviews with key stakeholders and a comparison of the documents with results from the interviews.The notation demonstrated to be suitable for two purposes:to improve the understanding of particular design events and as support material for presenting and exploring collaborations.Results indicate that the notation was suitable,comprehensible and flexible,and it demonstrated good value when used in speculative ways,such as an intermediary design artifact that supports discussion and improvements in the collaboration process,which indicates promising future directions.It can also be argued that,similar to a sketch,the notation can also support the process of planning and“designing”the interaction between teams in design fields and even in other project-based organizations.展开更多
Embedded systems used in real-time applications require low power, less area and high computation speed. For digital signal processing, image processing and communication applications, data are often received at a con...Embedded systems used in real-time applications require low power, less area and high computation speed. For digital signal processing, image processing and communication applications, data are often received at a continuously high rate. The type of necessary arithmetic functions and matrix operations may vary greatly among different applications. The RTL-based design and verification of one or more of these functions could be time-consuming. Some High Level Synthesis tools reduce this design and verification time but may not be optimal or suitable for low power applications. The design tool proposed in this paper can improve the design time and reduce the verification process. The design tool offers a fast design and verification platform for important matrix operations. These operations range from simple addition to more complex matrix operations such as LU and QR factorizations. The proposed platform can improve design time by reducing verification cycle. This tool generates Verilog code and its testbench that can be realized in FPGA and VLSI systems. The designed system uses MATLAB-based verification and reporting.展开更多
Based on analysis of electrochemical machining ( ECM) process and application of finite ele- ment technique ( FET) , a method of tool design is presented which can be used in ECM with passivated electrolyte. As a resu...Based on analysis of electrochemical machining ( ECM) process and application of finite ele- ment technique ( FET) , a method of tool design is presented which can be used in ECM with passivated electrolyte. As a result of specific treatment to boundary conditions, this method needs much less com- puting time and memory space. It has been shown that the theoretical results correspond well with the experimental ones .展开更多
The key techniques of modular design of heavy duty NC mathine tools are described. Amodule definition modelfor modular design and manufacturing of heavy duty NC machine tools isbulit and the essential composition of t...The key techniques of modular design of heavy duty NC mathine tools are described. Amodule definition modelfor modular design and manufacturing of heavy duty NC machine tools isbulit and the essential composition of the module definition model (MDM) is discussed in detail. Itis composed of two models: the part definition model (PDM) and the module assembly model(MAM). The PDM and MAM are built and their structures are given. Using object-oriented know-ledge representation and based on these models, an intelligent support system of modular design forheavy duty NC machine tools is developed and implemented This system has been applied to thepractical use of Wuhan Heavy Duty Machine Tool Works展开更多
AA5083 friction stir welds were produced using systematic experimental design, the process forces and heat input with varying parameters were studied. Helpful empirical models were developed in designing friction stir...AA5083 friction stir welds were produced using systematic experimental design, the process forces and heat input with varying parameters were studied. Helpful empirical models were developed in designing friction stir welding (FSW) tools and FSW welders. These models may be further helpful for making process parameter choice for this sort of alloy, defining welding program and control of process parameters by using computer numerical control friction stir welding welders. The results show that tool rotational speed, welding speed and tool shoulder diameter are most significant parameters affecting axial force and heat input, while longitudinal force is significantly affected by welding speed and probe diameter.展开更多
Complexity and implementation of design norms in Cameroon required a proven foreign expertise, but nowadays local engineers are mastering modern construction techniques. They are turning to pile foundations to solve t...Complexity and implementation of design norms in Cameroon required a proven foreign expertise, but nowadays local engineers are mastering modern construction techniques. They are turning to pile foundations to solve the problem of construction sites on weak soils. The objective of this work is to present the trend of the country pile-driving capacity of some foundations design and construction companies. The proposed analytical method is based on Finite Element Method and on the theory of wave's propagation and transmission along the pile taking into account experimental data on the construction site. The proposed method is validated through recorded data during the construction of the Mungo Bridge in Cameroon, and obtained analytical results are in agreement with experimental results.展开更多
Cylindrical rings with thin wall and high web ribs(CRTWHWR)are widely used as the key load bearing structures such as rocket body and space station cabin in aerospace field.However,it is still difficult to efficiently...Cylindrical rings with thin wall and high web ribs(CRTWHWR)are widely used as the key load bearing structures such as rocket body and space station cabin in aerospace field.However,it is still difficult to efficiently manufacture CRTWHWR with high performance because of their extreme geometry with thin-walled skins,high web ribs and large size.In this paper,a novel radial envelope forming process is put forward to efficiently achieve the plastic forming of CRTWHWR with high performance.Firstly,the principle of radial envelope forming process is clarified.Then,an efficient design method for the tool motion and geometry is proposed based on the reverse envelope principle,i.e.,CRTWHWR is adopted to reversely envelope the tool and thus the tool which does not interfere with CRTWHWR can be efficiently obtained in a single operation.Finally,a reasonable 3D FE model of the radial envelope forming process of CRTWHWR is established and the radial envelope forming mechanism of CRTWHWR is comprehensively revealed.Through the FE simulation and experiments with material of plastic mud,a typical CRTWHWR with diameter of 300 mm,axial height of 192 mm,the maximum rib height of 25 mm,the minimum rib thickness of 3 mm and skin thickness of 5 mm is radial envelope formed,i.e.,the ratio of the maximum rib height to the minimum rib thickness reaches 8.33,the ratio of the maximum rib height to skin thickness reaches 5 and the ratio of diameter to the minimum rib thickness reaches 100.The above results verify that the proposed radial envelope forming process has great potentials in efficiently manufacturing CRTWHWR with extreme geometry.展开更多
The presented work will show the highest relevance of solving all the issues related to this problem and present the results of the analysis of the main expected potential problems,which may occur in the implementatio...The presented work will show the highest relevance of solving all the issues related to this problem and present the results of the analysis of the main expected potential problems,which may occur in the implementation of the INDUSTRY-4.0 reform.It is proved that the pace and level of development of this reform will be determined to a large extent by the effectiveness of the individual nodes used and the entire mechatronic system.It has also been established that as a result of systematic miniaturization of the nodes of radio-electronic equipment and microelectronic equipment and microelectronic technology,the main problem of these reforms and the implementation of complex technological processes is instrumental and technological support,especially with cutting micro-tools and equipment.Therefore,on the example of these investigations,methods for improving their performance are shown.展开更多
Severaf researches show the environmental and microclfmatic benefits of the (ntegration of vegetation in architecture; however the potentialities of vertical and horizontal greening systems to retrofit buildings are ...Severaf researches show the environmental and microclfmatic benefits of the (ntegration of vegetation in architecture; however the potentialities of vertical and horizontal greening systems to retrofit buildings are still not much investigated. The retrofitting project of the Barsanti Institute of Camogli (Genoa, Italy) is presented, a building dated back to the sixties with serious architectural and efficiency problems, located in a considerable Landscape area. The development and application of a design tool (process tree), for horizontal and vertical greened surfaces, allows to evaluate the potentialities of vegetation to retrofit and to relate the encountered efficiency problems and the climate characteristics with the choice of plant species, system, and technology more suitable for the specific situation (of which environ- mental and economic impact are also evaluated) and to define a design approach for the systematic consideration of the many parameters involved. ~ 2013. Higher Education Press Limited Company. Production and hosting by Elsevier B.V. All rights reserved.展开更多
This article proposes a model for integrating environmental sustainability into architectural education that derives from the analysis of sustainable architectural design in practice.The research methodology is based ...This article proposes a model for integrating environmental sustainability into architectural education that derives from the analysis of sustainable architectural design in practice.The research methodology is based on nine case studies of architectural practices that are pioneers in environmentally sustainable design.The design process of a building from each practice was mapped using information gathered by interviews with the members of the design team,plans,diagrams and sketches.The case studies highlight the skills and knowledge that the architect needs to acquire to integrate sustainability into the design process.This reveals that architectural education might focus on developing attitudes,explicit knowledge,tacit knowledge and skills that interweave intuitive,analytical and social dimensions in a holistic manner.展开更多
As an application of artificial intelligence and expert system technology to database design,this paper presents an intelligent design tool NITDT,which comprises a requirements specification lan- guage NITSL,a knowled...As an application of artificial intelligence and expert system technology to database design,this paper presents an intelligent design tool NITDT,which comprises a requirements specification lan- guage NITSL,a knowledge representation language NITKL,and an inference engine with uncertainty reasoning capability.NITDT now covers the requirements analysis and conceptual design of database design.However,it is possible to be integrated with another database design tool, NITDBA,developed also at NIT to become an integrated design tool supporting the whole process of database design.展开更多
This paper proposes a generative approach for the automatic typesetting of books in desktop publishing.The presented system consists in a computer script that operates inside a widely used design software tool and imp...This paper proposes a generative approach for the automatic typesetting of books in desktop publishing.The presented system consists in a computer script that operates inside a widely used design software tool and implements a generative process based on several typographic rules,styles and principles which have been identified in the literature.The performance of the proposed system is tested through an experiment which included the evaluation of its outputs with people.The results reveal the ability of the system to consistently create varied book designs from the same input content as well as visually coherent book designs with different contents while complying with fundamental typographic principles.展开更多
Creep age forming(CAF)is an advanced forming technology that combines creep deformation and age hardening processes.When compared with the conventional forming technologies including roll bending and shot-peen forming...Creep age forming(CAF)is an advanced forming technology that combines creep deformation and age hardening processes.When compared with the conventional forming technologies including roll bending and shot-peen forming,CAF has many advantages of low residual stress,excellent dimensional stability,good service performance and short production cycle.It is an optimal technique for precise manufacturing for shape and properties of large-scale complicated thinwalled components of light-weight and high strength aluminum alloys in the aviation and aerospace industries.Nevertheless,CAF has an inevitable disadvantage that a large amount of springback occurs after unloading,which brings a challenge on the accurate shape forming and property tailoring of components.Therefore,how to achieve accurate prediction and control of springback has always been a bottleneck hindering the development of CAF to more industrial applications.After the factors of affecting springback and measures of reducing springback are summarized from the internal and external aspects,constitutive models for predicting springback and springback compensation methods for CAF of aluminum alloy panel components are reviewed.Then,a review of research progresses on tool design for CAF is presented.Finally,in view of the key issue that it is difficult to predict and control the shape and properties of components during CAF,the technical challenges are discussed and future development trends of CAF are prospected.展开更多
Friction stir welding (FSW) technology is being increasingly attractive in welding steels on account of the high-quality weld formation and excellent weld properties. The feasibility of FSW of steels has been convin...Friction stir welding (FSW) technology is being increasingly attractive in welding steels on account of the high-quality weld formation and excellent weld properties. The feasibility of FSW of steels has been convinced for nearly 20 years. However, the application progress for FSW of steels is slower than that of aluminum alloys owing to the high cost and poor usability of tools. The FSW tools are called as the heart of FSW process which is critical for welding quality control and the weld microstructure and properties. The recent progresses in research and development of FSW tools for welding steels have been reviewed. Material selections, geometry parameters, wear behavior and use life of the tools are summarized from the available literatures.展开更多
文摘In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel.
基金This research was supported by the KISTI Program(No.K-20-L02-C05-S01)the EDISON Program through the National Research Foundation of Korea(NRF)(No.NRF-2011-0020576).A grant was also awarded by the Ministry of Science and ICT(MSIT)under the Program for Returners for R&D.
文摘With the increase in research on AI(Artificial Intelligence),the importance of DL(Deep Learning)in various fields,such as materials,biotechnology,genomes,and new drugs,is increasing significantly,thereby increasing the number of deep-learning framework users.However,to design a deep neural network,a considerable understanding of the framework is required.To solve this problem,a GUI(Graphical User Interface)-based DNN(Deep Neural Network)design tool is being actively researched and developed.The GUI-based DNN design tool can design DNNs quickly and easily.However,the existing GUI-based DNN design tool has certain limitations such as poor usability,framework dependency,and difficulty encountered in changing GUI components.In this study,a deep learning algorithm that solves the problem of poor usability was developed using a template to increase the accessibility for users.Moreover,the proposed tool was developed to save and share only the necessary parts for quick operation.To solve the framework dependency,we applied ONNX(Open Neural Network Exchange),which is an exchange standard for neural networks,and configured it such that DNNs designed with the existing deep-learning framework can be imported.Finally,to address the difficulty encountered in changing GUI components,we defined and developed the JSON format to quickly respond to version updates.The developed DL neural network designer was validated by running it with KISTI’s supercomputer-based AI Studio.
基金supported by process No.2018/12304-8,FAPESP(Sao Paulo Research Foundation).
文摘Collaboration in large projects is a major challenge for contemporary architectural practice and this paper presents a notation for describing and analyzing how these collaborations can take place.Based on an extensive literature review some opportunities were found for the development of a notation that combined three particular aspects:network diagrams,Euler diagrams and a model from architectural design.An exploratory case study was conducted based on the collaboration during a complex architectural project,which combined three approaches:document analysis,semi-structured interviews with key stakeholders and a comparison of the documents with results from the interviews.The notation demonstrated to be suitable for two purposes:to improve the understanding of particular design events and as support material for presenting and exploring collaborations.Results indicate that the notation was suitable,comprehensible and flexible,and it demonstrated good value when used in speculative ways,such as an intermediary design artifact that supports discussion and improvements in the collaboration process,which indicates promising future directions.It can also be argued that,similar to a sketch,the notation can also support the process of planning and“designing”the interaction between teams in design fields and even in other project-based organizations.
文摘Embedded systems used in real-time applications require low power, less area and high computation speed. For digital signal processing, image processing and communication applications, data are often received at a continuously high rate. The type of necessary arithmetic functions and matrix operations may vary greatly among different applications. The RTL-based design and verification of one or more of these functions could be time-consuming. Some High Level Synthesis tools reduce this design and verification time but may not be optimal or suitable for low power applications. The design tool proposed in this paper can improve the design time and reduce the verification process. The design tool offers a fast design and verification platform for important matrix operations. These operations range from simple addition to more complex matrix operations such as LU and QR factorizations. The proposed platform can improve design time by reducing verification cycle. This tool generates Verilog code and its testbench that can be realized in FPGA and VLSI systems. The designed system uses MATLAB-based verification and reporting.
文摘Based on analysis of electrochemical machining ( ECM) process and application of finite ele- ment technique ( FET) , a method of tool design is presented which can be used in ECM with passivated electrolyte. As a result of specific treatment to boundary conditions, this method needs much less com- puting time and memory space. It has been shown that the theoretical results correspond well with the experimental ones .
文摘The key techniques of modular design of heavy duty NC mathine tools are described. Amodule definition modelfor modular design and manufacturing of heavy duty NC machine tools isbulit and the essential composition of the module definition model (MDM) is discussed in detail. Itis composed of two models: the part definition model (PDM) and the module assembly model(MAM). The PDM and MAM are built and their structures are given. Using object-oriented know-ledge representation and based on these models, an intelligent support system of modular design forheavy duty NC machine tools is developed and implemented This system has been applied to thepractical use of Wuhan Heavy Duty Machine Tool Works
文摘AA5083 friction stir welds were produced using systematic experimental design, the process forces and heat input with varying parameters were studied. Helpful empirical models were developed in designing friction stir welding (FSW) tools and FSW welders. These models may be further helpful for making process parameter choice for this sort of alloy, defining welding program and control of process parameters by using computer numerical control friction stir welding welders. The results show that tool rotational speed, welding speed and tool shoulder diameter are most significant parameters affecting axial force and heat input, while longitudinal force is significantly affected by welding speed and probe diameter.
文摘Complexity and implementation of design norms in Cameroon required a proven foreign expertise, but nowadays local engineers are mastering modern construction techniques. They are turning to pile foundations to solve the problem of construction sites on weak soils. The objective of this work is to present the trend of the country pile-driving capacity of some foundations design and construction companies. The proposed analytical method is based on Finite Element Method and on the theory of wave's propagation and transmission along the pile taking into account experimental data on the construction site. The proposed method is validated through recorded data during the construction of the Mungo Bridge in Cameroon, and obtained analytical results are in agreement with experimental results.
基金the National Natural Science Foundation of China(No.U2037204)the 111 Project(B17034)+1 种基金Innovative Research Team Development Program of Ministry of Education of China(No.IRT17R83)the National Natural Science Foundation of China(No.52005375)for the support given to this research。
文摘Cylindrical rings with thin wall and high web ribs(CRTWHWR)are widely used as the key load bearing structures such as rocket body and space station cabin in aerospace field.However,it is still difficult to efficiently manufacture CRTWHWR with high performance because of their extreme geometry with thin-walled skins,high web ribs and large size.In this paper,a novel radial envelope forming process is put forward to efficiently achieve the plastic forming of CRTWHWR with high performance.Firstly,the principle of radial envelope forming process is clarified.Then,an efficient design method for the tool motion and geometry is proposed based on the reverse envelope principle,i.e.,CRTWHWR is adopted to reversely envelope the tool and thus the tool which does not interfere with CRTWHWR can be efficiently obtained in a single operation.Finally,a reasonable 3D FE model of the radial envelope forming process of CRTWHWR is established and the radial envelope forming mechanism of CRTWHWR is comprehensively revealed.Through the FE simulation and experiments with material of plastic mud,a typical CRTWHWR with diameter of 300 mm,axial height of 192 mm,the maximum rib height of 25 mm,the minimum rib thickness of 3 mm and skin thickness of 5 mm is radial envelope formed,i.e.,the ratio of the maximum rib height to the minimum rib thickness reaches 8.33,the ratio of the maximum rib height to skin thickness reaches 5 and the ratio of diameter to the minimum rib thickness reaches 100.The above results verify that the proposed radial envelope forming process has great potentials in efficiently manufacturing CRTWHWR with extreme geometry.
基金This work was supported by Shota Rustaveli National Science Foundation(SRNSF)[PHDF-19-2224,Improving the efficiency of mechatronic systems in order to ensure the reform of“Industry-4.0”].
文摘The presented work will show the highest relevance of solving all the issues related to this problem and present the results of the analysis of the main expected potential problems,which may occur in the implementation of the INDUSTRY-4.0 reform.It is proved that the pace and level of development of this reform will be determined to a large extent by the effectiveness of the individual nodes used and the entire mechatronic system.It has also been established that as a result of systematic miniaturization of the nodes of radio-electronic equipment and microelectronic equipment and microelectronic technology,the main problem of these reforms and the implementation of complex technological processes is instrumental and technological support,especially with cutting micro-tools and equipment.Therefore,on the example of these investigations,methods for improving their performance are shown.
文摘Severaf researches show the environmental and microclfmatic benefits of the (ntegration of vegetation in architecture; however the potentialities of vertical and horizontal greening systems to retrofit buildings are still not much investigated. The retrofitting project of the Barsanti Institute of Camogli (Genoa, Italy) is presented, a building dated back to the sixties with serious architectural and efficiency problems, located in a considerable Landscape area. The development and application of a design tool (process tree), for horizontal and vertical greened surfaces, allows to evaluate the potentialities of vegetation to retrofit and to relate the encountered efficiency problems and the climate characteristics with the choice of plant species, system, and technology more suitable for the specific situation (of which environ- mental and economic impact are also evaluated) and to define a design approach for the systematic consideration of the many parameters involved. ~ 2013. Higher Education Press Limited Company. Production and hosting by Elsevier B.V. All rights reserved.
文摘This article proposes a model for integrating environmental sustainability into architectural education that derives from the analysis of sustainable architectural design in practice.The research methodology is based on nine case studies of architectural practices that are pioneers in environmentally sustainable design.The design process of a building from each practice was mapped using information gathered by interviews with the members of the design team,plans,diagrams and sketches.The case studies highlight the skills and knowledge that the architect needs to acquire to integrate sustainability into the design process.This reveals that architectural education might focus on developing attitudes,explicit knowledge,tacit knowledge and skills that interweave intuitive,analytical and social dimensions in a holistic manner.
文摘As an application of artificial intelligence and expert system technology to database design,this paper presents an intelligent design tool NITDT,which comprises a requirements specification lan- guage NITSL,a knowledge representation language NITKL,and an inference engine with uncertainty reasoning capability.NITDT now covers the requirements analysis and conceptual design of database design.However,it is possible to be integrated with another database design tool, NITDBA,developed also at NIT to become an integrated design tool supporting the whole process of database design.
基金This work is partially supported by the Foundation for Science and Technology,I.P./MCTES(Portugal)through national funds(PIDDAC),within the scope of project UIDB/00326/2020 or project code UIDP/00326/2020Sérgio M.Rebelo was funded by FCT under the grant SFRH/BD/132728/2017 and COVID/BD/151969/2021.
文摘This paper proposes a generative approach for the automatic typesetting of books in desktop publishing.The presented system consists in a computer script that operates inside a widely used design software tool and implements a generative process based on several typographic rules,styles and principles which have been identified in the literature.The performance of the proposed system is tested through an experiment which included the evaluation of its outputs with people.The results reveal the ability of the system to consistently create varied book designs from the same input content as well as visually coherent book designs with different contents while complying with fundamental typographic principles.
基金financial support from the Key Program of the National Natural Science Foundation of China (No.51235010)the National Science Fund for Excellent Young Scholars (No.51522509)the National Natural Science Foundation of China (NO.51905424)
文摘Creep age forming(CAF)is an advanced forming technology that combines creep deformation and age hardening processes.When compared with the conventional forming technologies including roll bending and shot-peen forming,CAF has many advantages of low residual stress,excellent dimensional stability,good service performance and short production cycle.It is an optimal technique for precise manufacturing for shape and properties of large-scale complicated thinwalled components of light-weight and high strength aluminum alloys in the aviation and aerospace industries.Nevertheless,CAF has an inevitable disadvantage that a large amount of springback occurs after unloading,which brings a challenge on the accurate shape forming and property tailoring of components.Therefore,how to achieve accurate prediction and control of springback has always been a bottleneck hindering the development of CAF to more industrial applications.After the factors of affecting springback and measures of reducing springback are summarized from the internal and external aspects,constitutive models for predicting springback and springback compensation methods for CAF of aluminum alloy panel components are reviewed.Then,a review of research progresses on tool design for CAF is presented.Finally,in view of the key issue that it is difficult to predict and control the shape and properties of components during CAF,the technical challenges are discussed and future development trends of CAF are prospected.
基金The authors are grateful to the National Natural Science Foundation of China (Grant Nos. 51325401 and U 1660201 ) and the National Magnetic Confinement Fusion Energy Research Project (Grant No. 2015GB 119001 ) for financial support.
文摘Friction stir welding (FSW) technology is being increasingly attractive in welding steels on account of the high-quality weld formation and excellent weld properties. The feasibility of FSW of steels has been convinced for nearly 20 years. However, the application progress for FSW of steels is slower than that of aluminum alloys owing to the high cost and poor usability of tools. The FSW tools are called as the heart of FSW process which is critical for welding quality control and the weld microstructure and properties. The recent progresses in research and development of FSW tools for welding steels have been reviewed. Material selections, geometry parameters, wear behavior and use life of the tools are summarized from the available literatures.