The emphasis of this guide is on industrial irradiation methodologies with a strong reference to existing literature and applicable standards. If the filament made of tungsten or lab 6 is heated with joule heat, the free electrons inside the filament acquire thermal energy to exceed the work function, which is the energy difference between an electron at the fermi level and that in vacuum. Temescal brand guns use the conventional mounting approach, while the integrated guns use an integrated feedthrough to route all connections through the a rotatable center mount with all the fittings. Electron beam characterization of a combined diode rf electron gun. Development of an electron gun design optimisation methodology. Field service and parts for airco temescal electron beam gun power supplies, electron beam guns, electron beam sweeps,deposition systems and helium leak detectors. Electron beam welding advantages,disadvantages and application introduction to e beam welding. The generation of a highly monochromatic and coherent electron beam is an important challenge in the design of modern electron microscopes. The following is a recount of my personal efforts in finding a stable source of 0.
Multi, single, and high performance emitters and parts. Characterisation of a novel electron beam gun design twi. Measurements are carried out for a beam with a power up to 4 kw and an electron energy of 60 kev. Our electron beam gun parts are in stock and our pricing is competitive. With 60 kw nonvacuum equipment singlepass welds can be made in metal thicknesses up to 25 mm. Closeup of the phosphorcoated inner side of the screen cathode ray tube electron gun. The source of the electron beam is the cathode, a flat metal support covered with oxides of barium and strontium. It consists of an electron gun, diaphragm, focusing lens, deflector coil, work table, etc. Electron beam machining equipment the basic functions of any electron beam gun are to generate free electrons at the cathode, accelerate them to a sufficiently high velocity and to focus them over a small spot size.
The electron gun with variable beam profile for optimization. The following is a recount of my personal efforts in finding a stable source of. Development of an electron gun design optimisation. Pdf on the beam parameters of an electron gun with a plasma. However, the forces between the electrons the space charge forces cause the beam to stop. Ion beam guns and electron beam guns selection guide. Pvd is more favorable to be used as compared to its counter part, cvd due to the reason of lower process risk and cheaper in material cost. By varying the potential of this electrode it is possible to obtain on the gun output the beam with parabolic, flat or hollow profile. Schematics and drawings adobe pdf format required to read prints. Design and numerical simulation of thermionic electron gun. Our more than 50 years of experience are reflected in over 400 electron beam systems installed worldwide.
Electron beam irradiation electron beam ebeam irradiation is a form of ionizing energy that is characterized by its low penetration and highdosage rates. In other words, it is a device used in crt for displaying the image on the phosphorous screen of crt. Electrons hit the workpiece and their kinetic energy is transformed to the thermal energy heating the metal so that the sides of the workpiece can be joined and a. In scanning electron microscopy visual inspection of the surface of a material utilizes signals of two types, secondary and backscattered electrons. Electron beam welding an overview sciencedirect topics. Secondary and backscattered electrons are constantly being produced from the surface of the specimen while under the electron beam however they are a result of two separate types of interaction. The electron gun with a control electrode was designed to produce hollow electron beams. Temescal simba 2 electron beam power supply multiple voltage and current ranges enhance the versatility of the simba 2.
Electron beam machining ebm diagram, working, advantages. Design of an electron gun using computer optimization. The gun includes a solid filament, gas, or liquid within a cathode which is excited via extreme heat or high voltage inside a vacuum. One commonality of these electron beam welders is that all beam parameters and all mechanical axes are numerically controlled either by a plc or a cnc. Apr 28, 2014 this feature is not available right now. Jan 06, 2015 electron beam machining equipment the basic functions of any electron beam gun are to generate free electrons at the cathode, accelerate them to a sufficiently high velocity and to focus them over a small spot size. Sheet beam is employed in thz devices as the beam offers an effective interaction with the rf signal.
Its target audience is readers who have a basic understanding of electron beam technology and want to evaluate and apply mathematical. This provides increased specific power of the beam and, as a result, the high capability to increase the penetration depth of welded joints. A strong history of reliable electron beam source ebeam gun power supplies is critical to process success. An experimental approach article pdf available in iranian journal of physics research 172. In short, electron beam evaporation is a process of evaporation of material that is to be used to deposit itself on the wafer substrate by using beam of electrons to evaporate heat it. Welding systems ebocam fixed gun electron beam welding systems ptrs eb chamber welders are modular systems built with proven designs using high quality offtheshelf components. We will discuss the application of these tools for the. Electron beam evaporation or also known as ebeam evaporation. In this paper, an electron gun was suggested that has an appropriate beam current, 200 ma, and a low level of beam loss in the e gun. Ferrotec offers electron beam sources in two mounting configurations, conventional temescal mount guns and integrated center mount guns.
Outofvacuum electron beam welding provided that the gun towork distance is less than about 35 mm to allow for the greater dispersion of the electron beam compared with working in a vacuum, it is possible to weld many materials out of vacuum. We offer power supplies for single source or multiple source operation. The well known slac electron trajectory program egun has been ported to pcs and has been developed into a family of programs for the design and the optimization of particle optics devices including electron and ion guns, beam transport sections and collectors. Pdf electron beam characterization of a combined diode rf. The beam a concentrated, highly charged stream of electrons is generated by accelerators capable of producing continuous or pulsed beams. A brief idea about the evolution of the electron gun components and their basis of functioning are also discussed. The schematic arrangement of electron beam machining ebm is shown in fig. This may take place under elevated temperatures and nitrogen atmosphere.
Electron beam additive manufacturing uses mostly two cathode filament materials, namely tungsten and lab 6. The electron gun emits electrons and forms them into a beam by the help of a heater, cathode, grid, preaccelerating, accelerating and focusing anode. The ebm machine uses an electron beam gun to melt metal powder at 70 micron layer thickness, and builds solid details that have homogeneous material structure. Like other techniques using am, this also creates objects layer by layer nasr et al. An electron gun also called electron emitter is an electrical component in some vacuum tubes that produces a narrow, collimated electron beam that has a precise kinetic energy. Electron beam melting an overview sciencedirect topics. Guns can be focusable for small spot size, for use in applications such as xray production, welding and rheed. It is several orders of magnitude smaller than the beam current. This type of deposition falls into the cateogry of pvd, physical vapor deposition. Method of controlling electron beam focusing of pierce type electron gun and control device therefor download pdf info publication number ep2077574b1. Use of mathematical modelling in electron beam processing. Ebm is an alternate additive metal process in comparison to dmls, and is a perfect solution for large parts built using ti6ai4v. The power supply operates in userselectable voltag e ranges of 3 to 7 kv and 6 to 10 kv. Characterisation of a novel electron beam gun design with a radio frequency excited plasma cathode pdf 936kb member report 10562015 twi industrial member report summary 10562015 by colin ribton, s del pozo and d r smith.
Figure 1b details two important aspects of an electron gun. Electron beam welding process, applications and equipment. Both materials have very specific characteristics as. Electron beam melting ebm is one of the latest am techniques using a computercontrolled electron gun to create fully dense 3d objects directly from metal powder. Electron beam welding parts, working, applications with pdf. Mar 31, 2017 first electron gun produces high velocity electron particles.
Electron gun, electrode structure that produces and may control, focus, and deflect a beam of electrons, as in a television picture tube see figure, where the beam produces a visual pattern on the tubes screen. First electron gun produces high velocity electron particles. The source of the electron beam is the cathode, a flat metal support covered with. Electrons hit the workpiece and their kinetic energy is transformed to the thermal energy heating the metal so that the sides of the workpiece can be joined and a weld can be formed after freezing. Electron beam welding ebw is a fusion welding in which coalescence is produced by heating the workpiece due to impingement of the concentrated electron beam of high kinetic energy on the workpiece.
The design of electron and ion guns, beams, and collectors. Index termselectron gun, thermionic emission, secondary emission, field emission, explosive electron emission. Find temescal, cha industries, and varian for sale on machinio. Further, the beam needs to be manoeuvred if required by the gun. The electron gun is the device in that it shoots off a continuous or pulsed stream of electrons.
Electron beam welding parts, working, applications with. The electron beam gun is located either inside the vacuum chamber or stationary on the outside figure 14. Mask for separating beams for red, green, and blue part of displayed image 7. Electron beam cathodes the vacuum level in the gun has a direct impact on the performance of the cathodes used in an electron beam gun.
The resulting electron gun are fabricating, and the gun s performance will be. As the electron beam impinges the workpiece, kinetic energy of. The electron gun is, mechanically and functionally, composed of two main parts. Electron beam welding is a welding process that uses the heat produced by a beam of high energy electrons. Development of an electron gun design optimisation methodology colin nigel ribton abstract the design of high quality electron generators to meet specific requirements is important in the application of these devices to a variety of materials processing systems including welding, cutting and additive. Conventional electron guns use thermal energy to emit electrons from the cathode. Ebocam fixed gun electron beam welding systems ptr. The electron beam formation, its focusing properties and the expansion and spreading of the beam over the collector surface need reliable tools for the design of magnetic shielding of solenoids as well as for the calculation of electron trajectories under the influence of electric, magnetic and self fields. The largest use is in cathode ray tubes crts, used in nearly all television sets, computer displays and oscilloscopes that are not flatpanel displays. Electron beam welding advantages,disadvantages and application. There are a series of lenses which take care of only convergent electron passes through it. The cathode is generally made of tungsten or tantalum.
Incoming voltage options make telemark power supplies suitable for all locations. Properties of electrons, their interactions with matter and. Ion beam guns and electron beam guns function differently based on the type of design, but all share the same principals of operation. Use of electron beam gun for hard rock excavation second quarterly technical report i 4 descriptive notes type ot report mnd indus ivr dales, quarterly technical report i april 30 june 1971 au thorisi firm name, middle initial, laal name david r. Construction and working of electron beam machining. The electrons themselves are created through a heating process coming from a hot filament. Furthermore, the design of the electron gun was verified using beam dynamics code egn2w and cstparticle studio 6,7. Our current eh150v, eh300v and eh800v electron beam guns are the most powerful in the world. Electron beam processing or electron irradiation ebi is a process that involves using electrons, usually of high energy, to treat an object for a variety of purposes. To test electron guns in the elephant vacuum chamber so that we as a team may obtain a means of testing our particle detectors used for the cascades 2 project. The electron gun is defined as the source of focused and accelerated electron beam. Temescal system schematics and parts list for power supplies. Design and analysis of an electron beam in an electron gun.
Outofvacuum electron beam welding provided that the guntowork distance is less than about 35 mm to allow for the greater dispersion of the electron beam compared with working in a vacuum, it is possible to weld many materials out of vacuum. These electron particles move towards anode which is placed after cathode tube. The brightness of a focused electron beam generated by a gun with a plasma emitter is measured. The gun design is based on the application of triode emission system with improved quality of electron beam formation. Laser heated electron beam gun optimization to improve. Machining inside the vacuum chamber construction of ebm. In this paper, an electron gun was suggested that has an appropriate beam current, 200 ma, and a low level of beam loss in the egun. Sheet beam gun design is a challenge in achieving required flatness and laminarity over the. Electron beam guns for high energy electron accelerators. Ep2077574b1 method of controlling electron beam focusing of. The electron beam then emerges from the gun assembly through an exit hole in the groundplane anode with an energy equal to the value of the negative high voltage gun operating voltage being applied to the cathode.
961 273 1264 54 97 1132 1162 1069 1579 986 207 304 749 1355 465 848 971 1278 310 1504 873 787 864 1246 702 140 1069 855 807 798 368 628 1240 645 1159