What is Radiant Energy Welding?
Definition: Radiant energy welding is a type of fusion welding process in which the heat required for joining of metals is obtained from the energy beam being focused on a workpiece.
There are two types of Radiant energy welding processes.
Let’s discuss each of these Radiant energy welding one by one.
#1) Electron Beam Welding
What is Electron Beam Welding? Electron beam welding is a fusion welding process in which the metals are joined due to heat produced by the collision of high-velocity electron beam with the metal.
The electron beam welding operation is performed under the vacuum chamber so that the dissipation of electron beam can be prevented.
How does electron beam welding work?
The complete setup for the electron beam welding is shown in the line diagram above.
On supplying a high voltage electric current, the electron beam is emitted from the electron gun.
These electrons have a very high speed and hence the electron beam possesses very high kinetic energy.
In order to focus the electron beam, the electromagnetic focusing lens are used (see above diagram).
Further, the focused electron beam is allowed to fall on the workpiece surface which is to be welded.
When this electron beam containing high kinetic energy strikes with the workpiece surface, the kinetic energy is converted into heat energy.
This heat energy is so high that it can melt the metal surface.
Due to this melting of the surface, the welding of the metal pieces takes place.
The electron beam is very narrow and it can create a high quality weld with a deep penetration.
Using electron beam welding, the holes (or penetration) having depth to width ratio of 20:1 can be achieved.
For detailed information on electron beam welding, you can refer to its main article: What is electron beam welding? (And how does it work?)
#2) Laser Welding
What is Laser Beam Welding? Laser welding (or laser beam welding) is a fusion welding process in which the joining of metals takes place due to heat produced by a laser beam.
In Laser beam welding, the laser acts as a concentrated heat source and it is focused on the weld region which melts the metal and welding takes place.
How does laser welding work?
The setup for the laser beam welding process is shown in the diagram above.
The laser beam used for laser welding can be generated by using either gas laser, liquid state laser or solid state laser.
Above diagram shows the solid state laser.
As shown in the schematic diagram, the ruby crystal is used to generate the light source.
The ruby crystal is surrounded by flash lamps. When the electric power is supplied, a high amount of light source is produced.
Now, the upper part of the ruby crystal is covered by the fully reflecting mirror. So all the light is reflected back.
The other mirror which is towards the down side is a partially reflecting mirror.
Because of the fully reflecting mirror (upper side) and partially reflecting mirror (downward side), the high density of the photon beam is generated (see the arrows in the image).
This high density photon beam (or laser beam) passes towards the focusing lens.
Because of the focusing lens, the laser beam is concentrated at the point on the weld surface.
This concentrated laser beam produces a very high amount of heat which can melt the metal surface easily.
The filler material (or filler wire) is used to fill the weld groove during the laser welding process.
For more information on the laser welding process, you can refer to its main article: What is laser beam welding? (And how does it work?)