Electron Beam Welding Process

 In EBW process, the heat is generated when the electron beam impinges on work piece. As the high velocity electron beam strikes the surfaces to be welded, their kinetic energy changes to thermal energy and hence causes the work piece metal to melt and fuse. A schematic setup of the electron beam welding is shown in Fig.  This process employs an electron gun in which the cathode in form of hot filament of tungsten or tantalum is the source of a stream of electrons.  The electrons emitted from filament by thermionic emission are accelerated to a high velocity to the anode because of the large potential difference that exists between them.  The potential differences that are used are of the order of 30 kV to 175 kV. The higher the potential difference, higher would be the acceleration. The current levels are low ranging between 50 mA to 1000 mA. The electron beam is focused by a magnetic lens system on the work pieces to be welded.

Process	Description
Electron Speed	The depth of penetration depends on the speed of electrons in the beam.
Accelerating Voltage	The accelerating voltage determines the speed of electrons in the beam.
Heat Conversion	When the high-velocity electron beam strikes the workpiece, the kinetic energy of the electrons is converted to heat.
Material Melting	The electrons penetrate the metal and cause the material in their path to melt.
Joint Formation	As the melted material cools down, it solidifies and forms a joint.
Depth of Penetration	The depth to which the electrons penetrate the metal depends on their speed and the accelerating voltage.
Beam Focusing	A magnetic lens system is used to focus the electron beam onto the workpieces.
Current and Voltage	The current levels used in electron beam welding are typically low, ranging from 50 mA to 1000 mA, while the potential differences (voltage) applied can be between 30 kV to 175 kV.