Vacuum Electron Beam Welding (EBW, Electron Beam Welding)
The basic working principle of vacuum electron beam welding is as follows:
The entire welding process needs to be carried out in a high vacuum chamber (with a vacuum degree ranging from 10⁻² to 10⁻⁵ Pa):
When the filament of the electron gun is heated and releases free electrons, through a high-voltage electric field for acceleration and precise focusing by electromagnetic lenses, a high-energy, high-speed electron beam will be formed.
At this time, the formed high-speed electrons will quickly collide with the joint area of the welding workpiece, converting their kinetic energy into high heat, and causing the local metal to rapidly melt and form a molten pool;The workpiece moves at a constant speed, and the molten pool cools and solidifies to form a dense weld seam, completing the sealing welding.
The vacuum environment can prevent the electron beam from being scattered by the air, isolate oxygen/nitrogen, avoid the oxidation and cracking of active metals such as niobium and titanium due to welding, and prolong the service life of these rare metal products.
Vacuum Electron Beam Welding Advantages
The weld depth-to-width ratio is extremely large: up to 60:1. The welds are narrow, with a large penetration depth. The sealing of thin plates only fuses the joint and will not burn through the shell.
The heat affected zone is extremely small: local instantaneous heating.
The overall deformation of titanium, niobium, and other active metal welded components is negligible, and it will not cause the head to expand or deform in size.
Vacuum isolation from oxidation: the entire process is in an oxygen-free environment. Welding high-purity niobium, tantalum, and titanium will not be oxidized or nitrided, ensuring the original high purity of the base material.
Precision control is possible: the beam flow is precisely controllable, allowing for precise sealing with micro-beams, suitable for sealing small niobium capsule shells.
High joint strength: The weld strength of niobium material can reach over 95% of the base material. The sealing performance is extremely strong, and helium inspection shows no leakage.
It can be welded with refractory metals (niobium, molybdenum, tungsten, tantalum), active metals, and dissimilar metals.
However, through vacuum electron beam welding, a sealed vacuum chamber is required, and if welding large components, it is prone to limitations; and the equipment cost is relatively high, suitable for the welding of precision and high-end sealing components.
If you need to weld some high-quality, precise and hard-to-melt metal parts, please feel free to contact us.
Contact person : Tracy
