The correct use of laser welding machine auxiliary gas

Laser welding machine is a very popular welding equipment in recent years, which has been maturely applied in many fields, such as automobile manufacturing, stainless steel kitchenware, household appliances, sanitary products and other fields. As a direction of laser application, laser welding machine has greater advantages compared with traditional welding equipment. In order to ensure that the handheld laser welding machine in the work to obtain good welding results, the correct use of auxiliary gas is very important. So what is the role of the auxiliary gas for laser welding? How should we correctly use the auxiliary gas?

The role of auxiliary gas for laser welding

1. The auxiliary gas can effectively protect the weld pool to reduce or even avoid being oxidized.

2. The correct blowing of auxiliary gas can effectively reduce the spatter produced during the welding of metal, thus protecting the focusing lens of the laser welding machine from the spattering of liquid droplets. Especially in the case of high-power laser welding, the protection of the lens is even more necessary because the spatter becomes very powerful.

3. The auxiliary gas can promote the uniform spread of the weld molten pool solidification, so that the weld molding uniformity and beauty.

4. The auxiliary gas is very effective in dispersing the plasma shielding produced by high-power laser welding, which can improve the effective utilization of the laser.

5. The use of nitrogen, argon as a protective gas, can be isolated from the oxygen, nitrogen and hydrogen in the air to prevent oxidation of the weld and produce porosity.

Auxiliary gases provide several positive effects for handheld laser welding machines, but if the wrong gas is selected it may cause cracks in the weld, which can reduce the robustness of the weld position. In addition to the wrong type of gas adversely affecting the weld, the wrong gas flow rate can also adversely affect laser welding. Whether the gas flow rate is too high or too low, the wrong gas blow-in flow rate can lead to more oxidation of the weld, and can also lead to serious interference with the weld metal in the weld pool by external forces resulting in a collapsed or unevenly shaped weld.

Auxiliary gas blowing in the wrong way will not only not play a protective and promotional role for the laser welding, and will even have a negative impact on the weld seam molding. Therefore, it is very important to choose the right auxiliary gas and the right blowing method for different metal welding processes.

The correct use of auxiliary gas

At present, there are two main ways of blowing in auxiliary gas, one is side blowing protective gas on the side axis; the other is coaxial protective gas. How to choose between the two types of blowing is decided through comprehensive consideration of various aspects, and it is generally recommended to use the side blowing of protective gas.

Types of auxiliary gases

Nitrogen

Nitrogen is the cheapest of the auxiliary gas, but the use of the process has limitations, not suitable for all laser welding process. For example, it is not used for certain types of stainless steel welding, mainly due to metallurgical problems. Such as absorption, which sometimes produces porosity in the lap zone.

Argon

Argon is denser and provides better protection and a smoother surface of the metal after welding. However, it is susceptible to high temperature metal plasma ionization, which will shield part of the beam to the workpiece, reducing the effective power of laser welding, and hindering the welding speed and depth of fusion.

Helium

Helium is very effective and not easily ionized, so it does not affect laser transmission and allows the laser to pass through smoothly. Helium allows the beam energy to reach the surface of the workpiece directly without hindrance and is highly resistant to oxidation. It is a more effective protective gas for laser welding machine welding operations, but helium is generally more expensive compared to other auxiliary gases.

We hope that you will use the correct auxiliary gas when operating your handheld laser welding machine. As long as the gas type, gas flow rate, blowing in the right way to choose, completely can get the ideal welding effect, but also will extend the service life of the laser welding machine.