Do hand-held welding products need air blowing?
Time:2022-06-06
Views:700
Do hand-held welding products need air blowing?
Why do laser welding machines use shielding gas?
There are three reasons.
Reason 1: it can protect the focusing lens from metal vapor pollution and liquid droplet sputtering
Shielding gas can protect the focusing lens of laser welding machine from metal vapor pollution and liquid droplet sputtering. Especially in high-power welding, it is more necessary to protect the lens because its ejecta become very powerful.
Reason 2: the shielding gas is very effective in dispersing the plasma shield generated by high-power laser welding
The metal vapor absorbs the laser beam to ionize into a plasma cloud, and the protective gas around the metal vapor will also ionize due to heating. If there is too much plasma, the laser beam will be consumed by the plasma to some extent. Plasma exists on the working surface as the second energy, which makes the penetration shallower and the weld pool surface wider.
The recombination rate of electrons is increased by increasing the collision of electrons with ions and neutral atoms, so as to reduce the electron density in the plasma. The lighter the neutral atom, the higher the collision frequency and the higher the recombination rate;
On the other hand, only the shielding gas with high ionization energy will not increase the electron density due to the ionization of the gas itself.
Reason 3: the protective gas can prevent the workpiece from oxidation during welding
The laser welding machine must use a kind of gas for protection, and the program should be set in the way that the protective gas comes out first and then the laser, so as to prevent the oxidation of the pulse laser during continuous processing.
The inert gas can protect the molten pool. When some materials can be welded without considering the surface oxidation, the protection can also be ignored. However, helium, argon, nitrogen and other gases are often used for most applications to protect the workpiece from oxidation during welding.
These are the reasons why shielding gas is used in laser welding. Shenzhen howweld reminds you that helium is generally used as the shielding gas to suppress the plasma to the greatest extent, so as to increase the penetration and welding speed; Moreover, it is light in weight and can escape, which is not easy to cause pores.
Of course, from our actual welding effect, the effect of argon protection is also good. Nitrogen is cheaper to use.
Of course, from our actual welding effect, the effect of argon protection is also good. Nitrogen is cheaper to use.