Electron beam machines, equipment or systems are used to process materials. Electron beams provide a very focused energy source with a very small wavelength. The small wavelength allows electron beams to image with greater resolution than light beams.
Electron beam processing is extremely precise and can be controlled to provide the specific cure needed for the application. This is accomplished using computer systems which control dosage and penetration depth of the electrons. The molecular changes result in strengthened polymers; increased abrasion resistance; increased chemical resistance; and additional memory for shrink film. Processing is typically nearly instantaneous and operates without the creation of emissions or air pollutants.
Electron beam processing systems are specified based on the beam energy, beam voltage, beam current and beam power. The energy of the electron beam is specified in volts (V), kilovolts (kV), electron volts (eV), kilo electron volts (keV), mega electron volts (MeV). An electric field is generated between the anode and cathode to accelerate the electron. The voltage of the electric field is the accelerating voltage. The higher the speed of the electrons, the smaller the wavelength and the higher the resolution. The energy will be more concentrated and the depth of penetration greater as voltage increases.
Lower electron volt systems (lower than 1MeV) are characterized by beam voltage and beam current. Higher electron volt systems are characterized by beam voltage and beam power. Beam output or beam power is specified in watts (W) or kilowatts (kW). Beam power is important for the degree of dosing as well as the level of melting or welding. The actual surface power density in watts per cubic meter (W/m3) is important for understanding the depth of penetration and size of the heat affected zone (HAZ). Electron beam welds have very small heat affected zone due to their high surface power density.
Electron beam processing systems are available for several different types of applications. Electron beam systems are generally tailored for specific applications. For instance, a electron beam system designed for welding titanium components together in a vacuum would be much different than a electron beam system for crosslinking plastic or curing a resin coating within a cloth or composite structure.