Polyacrylonitrile(PAN)/multi-walled carbon nanotubes(MWNTs)nanocomposites were prepared by an in-situ polymerization method and the fibers from these composites were obtained by a wet-spinning process.The orientation ...Polyacrylonitrile(PAN)/multi-walled carbon nanotubes(MWNTs)nanocomposites were prepared by an in-situ polymerization method and the fibers from these composites were obtained by a wet-spinning process.The orientation behavior of MWNTs in the PAN fibers was investigated by X-ray diffraction and sound velocity methods.The dispersion and the alignment of the nanotubes were also studied by scanning electron microscopy.展开更多
At present many CAD software products did not fully meet the requirements of National Standard 《Technical drafting and Mechanical Drawing》 that greatly affects the quality and speed of engineering design. Taking com...At present many CAD software products did not fully meet the requirements of National Standard 《Technical drafting and Mechanical Drawing》 that greatly affects the quality and speed of engineering design. Taking computer-aided design of typical mechanical parts as an example, this paper proposes an approach to develop corresponding functions in CAD software to enhance the standardization of engineering design.展开更多
This report gives a view of a computer multimedia book of mechanical drawing. This electronic book is developed under Windows and Chinese Star to form an integrated system on a CD-ROM. In the electronic book, graphics...This report gives a view of a computer multimedia book of mechanical drawing. This electronic book is developed under Windows and Chinese Star to form an integrated system on a CD-ROM. In the electronic book, graphics, images, 3D animation, audio, video and text techniques of computer multimedia are applied. The techniques, methods, contents and purpose of developing this system are introduced.展开更多
In order to overcome many problems and shortcomings of our three-dimensional design education in mechanical drawing, make the students master the modem design method and technology easily, modem modeling method and sh...In order to overcome many problems and shortcomings of our three-dimensional design education in mechanical drawing, make the students master the modem design method and technology easily, modem modeling method and shaping method are introduced, and the shaping designing methods of assembled-body are analyzed including basic requirements for shaping design, common principles of shaping and shaping design method. It will be helpful to improve the spatial imagination and modelling ability of student.展开更多
In order to improve the shaping design ability of students in mechanical drawing, it is necessary to introduce and analyze the shaping design of parts and some typical shaping method. Firstly, shaping designs of diffe...In order to improve the shaping design ability of students in mechanical drawing, it is necessary to introduce and analyze the shaping design of parts and some typical shaping method. Firstly, shaping designs of different structures of some parts such as installation part, connection part and so on are introduced, and then the shaping design procedure of the base of reducer is analyzed. Secondly, some typical shaping design methods such as shaping design based on the deformation of the basic body, profile design shaping design, complementary shaping design, equal volume shaping design, variation shaping design and combinatorial shaping design are introduced and analyzed. Finally, the design model of various pipe joints used in the exhibition hall is given as a design question. It will be helpful to improve the spatial imagination and shaping ability of students.展开更多
The present work demonstrates the effectiveness of combining the hydromechanical deep-drawing process with the Tailored Heat Treated Blank（THTB） technique. In the hydromechanical deep-drawing process, the fluid pres...The present work demonstrates the effectiveness of combining the hydromechanical deep-drawing process with the Tailored Heat Treated Blank（THTB） technique. In the hydromechanical deep-drawing process, the fluid pressure is used for postponing the fracture occurrence in the blank, while the THTB technique allows to create a material property gradient through a suitable artificial aging treatment carried out prior to the forming process. Since the number of process variables is large, in the present work the authors propose an optimization loop for the determination of the parameters controlling the extension of the blank regions to be subjected to the aging treatment and the temperature levels to be set during the heat treatment. The proposed methodology couples a simple finite element model（Abaqus） with a multiobjective optimization platform（mode FRONTIER）. A preliminary experimental campaign was carried out for determining the effect of the aging treatment on the mechanical（through tensile tests） and deformative（through formability tests）behavior of the AC170 PX aluminum alloy. Optimization results prove the effectiveness of the adopted methodology and put in evidence that the adoption of properly aged blanks in the hydromechanical deep drawing allows to increase the limit drawing ratio and to simplify the process since it is conducted at room temperature.展开更多
基金the Action on Scientists and Engineers to Serve Enterprises,China(No.2009GJE20016)Natural Science Foundation of Shanghai,China(No.09ZR1401500)+1 种基金Shanghai Leading Academic Discipline Project,China(No.B603)Program of Introducing Talents of Discipline to Universities,China(No.111-2-04)
文摘Polyacrylonitrile(PAN)/multi-walled carbon nanotubes(MWNTs)nanocomposites were prepared by an in-situ polymerization method and the fibers from these composites were obtained by a wet-spinning process.The orientation behavior of MWNTs in the PAN fibers was investigated by X-ray diffraction and sound velocity methods.The dispersion and the alignment of the nanotubes were also studied by scanning electron microscopy.
文摘At present many CAD software products did not fully meet the requirements of National Standard 《Technical drafting and Mechanical Drawing》 that greatly affects the quality and speed of engineering design. Taking computer-aided design of typical mechanical parts as an example, this paper proposes an approach to develop corresponding functions in CAD software to enhance the standardization of engineering design.
文摘This report gives a view of a computer multimedia book of mechanical drawing. This electronic book is developed under Windows and Chinese Star to form an integrated system on a CD-ROM. In the electronic book, graphics, images, 3D animation, audio, video and text techniques of computer multimedia are applied. The techniques, methods, contents and purpose of developing this system are introduced.
基金Supported by 2015 Undergraduate Education and Teaching Reform and Research Project of University of Science and Technology Beijing(JG2015M15)Fundamental Research Funds for the Central Universities(FRF-BR-15-047A)
文摘In order to overcome many problems and shortcomings of our three-dimensional design education in mechanical drawing, make the students master the modem design method and technology easily, modem modeling method and shaping method are introduced, and the shaping designing methods of assembled-body are analyzed including basic requirements for shaping design, common principles of shaping and shaping design method. It will be helpful to improve the spatial imagination and modelling ability of student.
基金Supported by 2015 Undergraduate Education and Teaching Reform and Research Project of University of Science and Technology Beijing(JG2015M15)2014 Education and Teaching Reform and Research Project of University of Science and Technology Beijing(JG2014M22)
文摘In order to improve the shaping design ability of students in mechanical drawing, it is necessary to introduce and analyze the shaping design of parts and some typical shaping method. Firstly, shaping designs of different structures of some parts such as installation part, connection part and so on are introduced, and then the shaping design procedure of the base of reducer is analyzed. Secondly, some typical shaping design methods such as shaping design based on the deformation of the basic body, profile design shaping design, complementary shaping design, equal volume shaping design, variation shaping design and combinatorial shaping design are introduced and analyzed. Finally, the design model of various pipe joints used in the exhibition hall is given as a design question. It will be helpful to improve the spatial imagination and shaping ability of students.
文摘The present work demonstrates the effectiveness of combining the hydromechanical deep-drawing process with the Tailored Heat Treated Blank（THTB） technique. In the hydromechanical deep-drawing process, the fluid pressure is used for postponing the fracture occurrence in the blank, while the THTB technique allows to create a material property gradient through a suitable artificial aging treatment carried out prior to the forming process. Since the number of process variables is large, in the present work the authors propose an optimization loop for the determination of the parameters controlling the extension of the blank regions to be subjected to the aging treatment and the temperature levels to be set during the heat treatment. The proposed methodology couples a simple finite element model（Abaqus） with a multiobjective optimization platform（mode FRONTIER）. A preliminary experimental campaign was carried out for determining the effect of the aging treatment on the mechanical（through tensile tests） and deformative（through formability tests）behavior of the AC170 PX aluminum alloy. Optimization results prove the effectiveness of the adopted methodology and put in evidence that the adoption of properly aged blanks in the hydromechanical deep drawing allows to increase the limit drawing ratio and to simplify the process since it is conducted at room temperature.
