In thermionic emission, electrons are produced by applying output voltage and filament current. From that we can calculate kinetic energy of electrons. What will be the temperature of the incident beam that are produced. How do I convert the kinetic energy of the beam to temperature.
If I know the temperature could I correlate the ingot temperature by hitting the electron beam in EB-PVD system.
to estimate the temperature equivalent I would just say 1/2mv^2 =kT they are probably far below relativistic velocities.
the temperature of the target you hit has however nothing to do with this. It is simply given by the equliberum of heating power (by the beam) heat dissipation (curibel cooling) heat irradiation (from the source) and evaporation enthalpy. that is hard to calculat, I see no reson why one would like to do that :-)
The temperature of an electron beam is defined by the statistical spread in energy due to thermionic emission. These statistics follow the Maxwell-Boltzmann distribution f = e^(−E/kT) as long as the beam is populated primarily by electrons that are above the Fermi energy.
to estimate the temperature equivalent I would just say 1/2mv^2 =kT they are probably far below relativistic velocities.
the temperature of the target you hit has however nothing to do with this. It is simply given by the equliberum of heating power (by the beam) heat dissipation (curibel cooling) heat irradiation (from the source) and evaporation enthalpy. that is hard to calculat, I see no reson why one would like to do that :-)
Thee is no need to convert the kinetic energy to beam temperature. The beam energy is deposited in the near surface of the ingot. A small volume of the ingot is heated enough to vaporize the material. The ingot temperature beyond the vaporizing volume is not of interest unless there are structural problems. The temperature in the vaporizing volume is the vaporization temperature.
Why do you need the ingot temperature? Do you mean the total ingot?
Kinetic theory tprovides a microscopic explanation of temperature, based on macroscopic systems' being composed of many microscopic particles, such as molecules and ions of various species, the particles of a species being all alike. It explains macroscopic phenomena through the classical mechanics of the microscopic particles. The equipartition theorem of kinetic theory asserts that each classical degree of freedom of a freely moving particle has an average kinetic energy of kBT/2 where kB denotes Boltzmann's constant. The translational motion of the particle has three degrees of freedom, so that, except at very low temperatures where quantum effects predominate, the average translational kinetic energy of a freely moving particle in a system with temperature T will be 3kBT/2.
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