Since its first introduction to the industry the control systems of electron beam machines have gone through an enormous evolution.With the availability of fast amplifier components and digital beam controllers the ad...Since its first introduction to the industry the control systems of electron beam machines have gone through an enormous evolution.With the availability of fast amplifier components and digital beam controllers the advantages of the electron beam have further increased making it a truly software controlled thermal processing tool.Modern beam controllers enable multi-beam and multi-focus technologies,where the beam is split in up to 60 individual beams.These technologies can reduce the processing time by parallel processing or improve the quality by optimized thermal expansion of the part.Multi-process technologies,where several processes are performed in one run (e.g.welding and cosmetic treatment) further extend the application range of the electron beam process.Fast beam deflection in conjunction with electron-optical monitoring is the fundamental component for advanced seam tracking systems.They allow automating the EB application in order to optimize the process costs and improve the quality of the re-sults in a reproducible manner.Basis for a high quality of the EB process is the condition of the tool,the electron beam itself.By in-troducing the beam parameter product to the electron beam,reliable information about the quality of the beam can be derived.Im-plemented into automatic beam alignment systems repeatable results with high quality are achieved.展开更多
The electron beam is an excellent welding tool.During years this powerful beam guarantees high performance welds in automotive,aviation and other industries.Due to its excellent parallel seam quality this welding tool...The electron beam is an excellent welding tool.During years this powerful beam guarantees high performance welds in automotive,aviation and other industries.Due to its excellent parallel seam quality this welding tool is often used for well-prepared gapless joints.Powerful fixtures have to guarantee the well-defined positioning of the work piece.However,tolerances in the work piece or the loading mechanism can cause misalignments.High quality welds frequently do not allow those misalignments.Consequently operators have to take care that the beam is proper positioned before welding.With joint tracking systems it is possible to automate those manual manipulations.The production gets more independent on adjustments by the operator.CCD cameras or electrodes for backscattered electrons for joint tracking systems need directly access to the joint.In many applications the fixture is in between the work piece and the measuring device.The joint cannot be automatically detected.Furthermore the positioning of the electrodes for backscattered electrons gives a major impact to the quality of the measurement.It becomes mandatory to integrate the joint detection into the fixture.The usage of backscattered electrons for seam tracking requests the integration of electrodes into the fixture.The fast beam deflection for electron beams opens a wide range of opportunities.Electron optical viewing improves the visualization of the work piece.Multi pool applications or surface modifications can increase the production capacity or achieve better product performance.Joint tracking can be performed offline or online.The free programmable environment allows combining tasks to match the production demands.Examples will be used to illustrate individual applications.展开更多
In the electron moiré method, a high-frequency grating is used to measure microscopic deformation, which promises significant potential applications for the method in the microscopic analysis of materials. Howeve...In the electron moiré method, a high-frequency grating is used to measure microscopic deformation, which promises significant potential applications for the method in the microscopic analysis of materials. However, a special beam scanning control device is required to produce a grating and generate a moiré fringe pattern for the scanning electron microscope （SEM）. Because only a few SEMs used in the material science studies are equipped with this device, the use of the electron moiré method is limited. In this study, an electron moiré method for a common SEM without the beam control device is presented. A grating based on a multi-scanning concept is fabricated in any observing mode. A real-time moiré pattern can also be generated in the SEM or an optical filtering system. Without the beam control device being a prerequisite, the electron moiré method can be more widely used. The experimental results from three different types of SEMs show that high quality gratings with uniform lines and less pitch error can be fabricated by this method, and moiré patterns can also be correctly generated.展开更多
文摘Since its first introduction to the industry the control systems of electron beam machines have gone through an enormous evolution.With the availability of fast amplifier components and digital beam controllers the advantages of the electron beam have further increased making it a truly software controlled thermal processing tool.Modern beam controllers enable multi-beam and multi-focus technologies,where the beam is split in up to 60 individual beams.These technologies can reduce the processing time by parallel processing or improve the quality by optimized thermal expansion of the part.Multi-process technologies,where several processes are performed in one run (e.g.welding and cosmetic treatment) further extend the application range of the electron beam process.Fast beam deflection in conjunction with electron-optical monitoring is the fundamental component for advanced seam tracking systems.They allow automating the EB application in order to optimize the process costs and improve the quality of the re-sults in a reproducible manner.Basis for a high quality of the EB process is the condition of the tool,the electron beam itself.By in-troducing the beam parameter product to the electron beam,reliable information about the quality of the beam can be derived.Im-plemented into automatic beam alignment systems repeatable results with high quality are achieved.
文摘The electron beam is an excellent welding tool.During years this powerful beam guarantees high performance welds in automotive,aviation and other industries.Due to its excellent parallel seam quality this welding tool is often used for well-prepared gapless joints.Powerful fixtures have to guarantee the well-defined positioning of the work piece.However,tolerances in the work piece or the loading mechanism can cause misalignments.High quality welds frequently do not allow those misalignments.Consequently operators have to take care that the beam is proper positioned before welding.With joint tracking systems it is possible to automate those manual manipulations.The production gets more independent on adjustments by the operator.CCD cameras or electrodes for backscattered electrons for joint tracking systems need directly access to the joint.In many applications the fixture is in between the work piece and the measuring device.The joint cannot be automatically detected.Furthermore the positioning of the electrodes for backscattered electrons gives a major impact to the quality of the measurement.It becomes mandatory to integrate the joint detection into the fixture.The usage of backscattered electrons for seam tracking requests the integration of electrodes into the fixture.The fast beam deflection for electron beams opens a wide range of opportunities.Electron optical viewing improves the visualization of the work piece.Multi pool applications or surface modifications can increase the production capacity or achieve better product performance.Joint tracking can be performed offline or online.The free programmable environment allows combining tasks to match the production demands.Examples will be used to illustrate individual applications.
基金The project supported by the National Natural Science Foundation of China (10662005)JSPS fellowship in Japan.
文摘In the electron moiré method, a high-frequency grating is used to measure microscopic deformation, which promises significant potential applications for the method in the microscopic analysis of materials. However, a special beam scanning control device is required to produce a grating and generate a moiré fringe pattern for the scanning electron microscope （SEM）. Because only a few SEMs used in the material science studies are equipped with this device, the use of the electron moiré method is limited. In this study, an electron moiré method for a common SEM without the beam control device is presented. A grating based on a multi-scanning concept is fabricated in any observing mode. A real-time moiré pattern can also be generated in the SEM or an optical filtering system. Without the beam control device being a prerequisite, the electron moiré method can be more widely used. The experimental results from three different types of SEMs show that high quality gratings with uniform lines and less pitch error can be fabricated by this method, and moiré patterns can also be correctly generated.
