22 May 2017

Electron beam welding advantages and disadvantages

Electron beam welding is a powerful beam welding process. The heat source in electron beam welding for melting joints is a focused beam of high-velocity electrons. The electron beam upon impinging on the workpiece releases the necessary heat by converting its kinetic energy. 

Electron beam welding is a fusion welding process in which a beam of high-velocity electrons is applied to two materials to be joined. It is often performed under vacuum conditions to prevent dissipation of the electron beam. Let us have a deep insight into the pros and cons of electron beam welding in this article. 

Advantages of electron beam welding :

  • No gas contamination.
  • Deepest weld penetration.
  • The depth-to-width ratios between 10:1 to 30:1 can be easily realized with electron beam welding.
  • It is done in a vacuum environment so clean welding environment is guaranteed.
  • Small heat affected zone similar to laser beam welding.
  • It allows welding of titanium, refractory metals and flammable metals.
  • Widely used in many industries.
  • Filler metal or flux are not needed to be used in this process of welding.
  • No additional processing is required.
  • The process can be used at higher welding speeds, typically between 125 to 200 mm/s.
  • It is also possible to closely control this penetration by controlling the accelerating voltage, beam current and beam focus. 
  • The heat liberated is low and also is in a narrow zone. Thus, the heat-affected zone is minimal as well as weld distortion is eliminated.

Disadvantages of electron beam welding :

  • Due to vacuum enclosure, high initial set up cost.
  • Size is restricted by a vacuum chamber only small to medium size items can be welded.
  • Sometimes this process required complex tooling.
  • X-rays generated during welding.
  • Longer cycle time than laser beam welding so this process is time-consuming.