Pulsed or continuous laser?
Your laser welding machine can be equipped with one of the following two types of lasers: a pulsed laser or a continuous laser. The choice of one over the other depends on the thickness of the material you want to weld.
The pulsed laser:
It is suitable for metals that are light and thin.
It prevents them from being deformed or melted.
This type of pulsed laser is mainly used to weld sheet metal, razor blades, gold jewelry chain links, and titanium pacemakers.
The continuous laser:
It is recommended for welding thick parts.
It is particularly effective in refractory metals.
It can pose problems if it is used on metal or a part that is too thin. In these cases, the laser could damage, deform, or melt the part.
It is more expensive than a pulsed laser, but it also reduces operating costs.
Laser welding machines have several advantages:
They are very fast:
The laser allows the metal to be heated extremely quickly while limiting the risk of deformation.
This technology is particularly effective for welding large quantities of sheet metal and is therefore widely used in the automotive industry.
They are also highly accurate:
They allow a localized, very fine, very clean, almost invisible welding.
They are particularly suitable for welding small parts.
This type of welding is very popular in the dental and jewelry industries as it provides the most aesthetic welding possible.
It is also possible to split the laser beam into several beams to provide welding that is even more accurate.
They can be adapted to a wide variety of part shapes and materials:
Laser welding machines are mainly used to weld metals, including refractory metals.
It is also possible to weld non-metallic parts with them, such as porcelain and glass.
You can use them to weld parts with very different shapes.
They do not wear out:
Laser welding machines operate without contact, so there is no risk of wear and tear on the machine.
There is also no need to change tools or electrodes, which is a definite advantage in terms of waste reduction.
They can be given orders digitally:
It is now possible to control the quality of the welding from a computer during the welding process.
The high level of automation allowed by such a process also makes it possible to detect and solve any quality problems.
However, it should be noted that laser welding machines also have certain disadvantages:
The costs of installing laser equipment are still very high.
This technology requires high assembly accuracy during processing to avoid laser beam deflections on the parts.
The laser weld is thinner than that obtained with electron beams, making the process unsuitable for welding high reflective metal.
Laser welding machine advantages:
Speed
Precision
Flexibility
Durability
Automation
How to choose the laser beam source?
There are three types of sources: fiber laser, CO2 laser, and Nd: YAG laser. The choice of the source depends on the type of laser you have chosen (pulsed or continuous).
The fiber laser:
This technology is based on sharp and thin beams that allow continuous and penetrative work to be carried out.
Like the CO2 laser, the fiber laser can penetrate thick sheets with great speed and efficiency.
It is easier to integrate into a machine than other lasers both in terms of use and maintenance.
This laser offers an average efficiency of 25%.
The CO2 laser:
This technology uses a gas mixture of carbon dioxide, helium, and nitrogen that is electrically-excited and optimized for continuous operation.
Like the fiber laser, the CO2 laser can penetrate thick sheets with great speed and efficiency.
It is more effective at penetrating thick steel parts than the fiber laser so it is more widely used.
It is more flexible and can penetrate thicker and lighter materials than the fiber laser.
This laser offers an average efficiency of 7% for 8,000 W.
The Nd: YAG laser:
It allows effective control of the power, duration, and shape of the laser pulses.
It is optimized for the pulsed mode.
But it emits pulses of very different wavelengths that do not all reach their target and then dissipate in the form of heat.
This type of laser is less energy efficient (3 to 4% efficiency) than CO2 lasers (7 to 10%) and fiber lasers (25 to 30%).
What parameters should be checked?
Before using your laser welding machine, you will need to verify several parameters. Here are some common precautions to take to ensure that your welding operations are a success.
Adjust energy
It is important to adjust the energy appropriately to adapt the power to the process.
This will prevent energy waste.
Ensure that you have the correct beam diameter
The diameter affects the welding performance.
We recommend that you choose a laser beam with a diameter between 0.2 and 2 mm.
Check the pulse frequencies
Pulse frequencies that are too high result in pulse energies that are too low making the welding less efficient or even inefficient.
Monitor the waveform of laser pulses
We recommend that you change the waveform according to the metal you intend to weld.
If you use an inadequate waveform, 60% to 98% of the laser energy will be lost and your welding operation will fail.
Which configuration should I choose for my welding machine?
There are 3 types of configurations available for welding machines:
Manual configuration
Semi-automatic configuration
Automatic configuration
The choice of configuration depends on:
Your production (small-scale or large?)
How you want to arrange your workstation
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