Discover the method of electromagnetic welding

Electric Beam Machining (EBM) is the process of thermally changing the kinetic energy of an electron into heat at a higher rate, so by locally heating we can proceed in many directions. Thermal processing. Use this method to process hard-to-work details using traditional methods. In particular, electronic beam welding technology is superior in processing hard materials, fireproof and other ceramic materials.

Welding is carried out electronically with a large cross-sectional area of ​​several tens to hundreds of millimeters, but the energy density is about 105, 107 W / cm2 and the power consumption is high. hundreds to several tens of Kw. This beam is projected onto the junction between the components and heated to the melting point. A clean, electronically-free beam of electrons, impurities and oxides. Welding power is smaller than other welding methods due to the high concentration of energy at the center of the electron beam.
Electronic welding equipment for welding metal can be divided into two types:
- Low voltage equipment, working with accelerating voltage up to 15 - 20 kV.
- High voltage equipment, working with accelerating voltage up to 150 - 200 kV.
The structure of electronic beam welding equipment is not much different than that of electron beam equipment used in other technologies. Some special parts of the device are: vacuum chamber with vacuum pump system, electronic launcher with high voltage DC.
Vacuum chambers are usually equipped with a cooling water system, a power supply system for cathodes, a magnetic induction system ... Vacuum chambers are equipped with special doors to be able to put the machining parts and Tools for the technological process. In addition, the chamber is equipped with vacuum gauges in different parts of the chamber.
Typically, the depth of the molten metal when electron beam welding can reach about 20 times greater than the welding width. Hence the metal's ability to stick to depth is better than width. The depth of the molten metal when soldering depends on the voltage V, the current I, the welding speed and the melting point of the metal.
An important characteristic of electron-beam welding is the very high heating and cooling rates. The heating speed can reach 7000oC / s and coolant speed is 1200oC / s. Due to the high concentration of energy, the heating rate and the rapid cooling rate, the heat of the surrounding areas is relatively low. Normally, the temperature in the area of ​​1.5mm thick is not higher than 400oC. should not affect deformation.
If the trace size of the electron beam is from a few centimeters to one millimeter, it does not require a high concentration of energy, the typical low voltage is 15-20kV. On the contrary, if the requirement for large concentration of energy to reach a small welding spot, a working voltage of 150-200 kV is required.
Electron beam welding does not necessarily involve the use of equipment to avoid the effects of a jet of heat that is more than 1mm thick. If the weld is less than 1mm, the technical condition will be more complicated, so you need to have a device to prevent jealousy.
In general, electron beam welding uses less energy than other methods. This can be explained by the ability to focus energy on the welding position. Because the size of the weld can reach about 10mm, the energy density can reach 107 - 109 W / cm2, which is much higher than the arc welding method (density is about 103 - 105W / cm2). ) and steam (density of 102 - 104W / cm2).