Electron-Beam Machining Equipment
– EBM equipment is similar to electron beam welding machines.
– EBM machines use voltages in the range of 150 to 200 kV.
– Magnetic lenses are used to focus the electron beam.
– Electromagnetic deflection systems position the beam as needed.
– Computers are often used to control EBM machines.
Considerations for Electron-Beam Machining
– Vacuums are necessary to reduce contamination and electron collisions with air molecules.
– EBM is best suited for small parts due to the requirement of working in a vacuum.
– The interaction of the electron beam with the work piece produces hazardous x-rays.
– Only highly trained personnel should use EBM equipment.
– Safety precautions must be taken to protect operators from radiation exposure.
Electron Beam Technology
– EBM is a form of electron beam technology.
– Electron beam technology utilizes high-velocity electrons concentrated into a narrow beam.
– The electron beam is directed towards the work piece, creating heat and vaporizing the material.
– EBM is used for precise cutting or boring of various metals.
– EBM offers better surface finish and narrower kerf width compared to other thermal cutting processes.
References for Electron-Beam Machining
– Website: https://web.archive.org/web/20070519165757/http://www.eod.gvsu.edu/eod/manufact/manufact-284.html
– Book: ‘Manufacturing Engineering and Technology’ by Serope Kalpakjian and Steven Schmid (2006)
– EBM is discussed on pages 854-855 of the book.
– The book provides valuable information on EBM processes and applications.
– These references can be consulted for further in-depth knowledge on EBM.
Electron-Beam Machining Applications
– EBM is best suitable for high melting point and high thermal conductivity materials.
– The EBM beam is operated in pulse mode, with pulse durations ranging from 50 μs to 15 ms.
– Beam current directly affects the energy per pulse, ranging from 200 μamp to 1 amp.
– Higher beam current and pulse duration result in increased energy per pulse.
– High-energy pulses can be used to machine larger holes on thicker plates. Source: https://en.wikipedia.org/wiki/Electron-beam_machining
This article includes a list of references, related reading, or external links, but its sources remain unclear because it lacks inline citations. (April 2009) |
Electron-beam machining (EBM) is a process where high-velocity electrons concentrated into a narrow beam that are directed towards the work piece, creating heat and vaporizing the material. EBM can be used for very precise cutting or boring of a wide variety of metals. Surface finish is better and kerf width is narrower than those for other thermal cutting processes.
EBM process is best suitable for high melting point and high thermal conductivity materials.
The EBM beam is operated in pulse mode. This is achieved by appropriately biasing the biased grid located just after the cathode. Switching pulses are given to the bias grid so as to achieve pulse duration of as low as 50 μs to as long as 15 ms. Beam current is directly related to the number of electrons emitted by the cathode or available in the beam. Beam current can be as low as 200 μamp to 1 amp. Increasing the beam current directly increases the energy per pulse. Similarly, increase in pulse duration also enhances energy per pulse. High-energy pulses (in excess of 100 J/pulse) can machine larger holes on thicker plates. The energy density and power density is governed by energy per pulse duration and spot size. Spot size, on the other hand is controlled by the degree of focusing achieved by the electromagnetic lenses. If a higher energy density is combined with a smaller spot size, the material removal would be faster though the size of the hole would be smaller. The plane of focusing would be on or just beneath the surface of the work piece. The electron beam is generated by the potential difference between the negatively-charged cathode and the positively-charged anode.
