Aluminum is a strong material with excellent corrosion resistance. Welding this material with conventional methods is typically very hard, so many people ask whether laser welding machines can weld aluminum.
Yes, laser welding is practical in welding aluminum material. The high energy and highly focused laser beam melts the material quickly without letting the heat dissipate. When it does not disperse, the filler or any other material fuses with aluminum strongly.
However, it is essential to mention that laser welding aluminum is not easy. Only experienced workers can effectively weld without causing aluminum to create pores.
Is It Possible Weld Aluminum with Lasers?
Yes, it is indeed possible to weld aluminum using lasers. A highly concentrated, high-energy beam of laser melts the aluminum very quickly. It does not allow the heat to dissipate. So, the melted aluminum fuses with other materials speedily and makes strong bonds.
However, it would be best to remember that High-power continuous wave (CW) lasers will work more effectively with the welds. The consistently high burst of heat will speedily melt the aluminum, and fusing any other material with aluminum quickly becomes more effortless.
Although you can use the pulsed lasers, their effectiveness will be slightly compromised. The continuous wave is very effective as it consistently puts heat on the aluminum. Eventually, aluminum melts and fuses with other elements.
When you use a pulsed laser welding machine, the chances are high that heat will dissipate. If that happens, pores will be made in the HAZ (heat-affected zone), affecting the strength of aluminum welding. That’s why I suggest using CW lasers to weld the aluminum.
Factors to Consider Before Laser Welding of Aluminum
It would help to remember that laser welding aluminum is a complex process. Small factors such as the alloy composition, surface conditions, and joint designs significantly influence the welding quality. The section below will mention some essential factors you must consider during or before welding the aluminum.
1- Alloy composition
Generally, aluminum is present in its alloy composition. 100% pure aluminum is rare. When welding, knowing how much and what types of other metals are mixed with aluminum is essential.
Some alloys respond better to laser welding than others. If you weld without knowing the alloy’s properties, you will get weaker or too bold welds that look bad. If the alloy present has a very high melting point, it would be tough to weld aluminum in that situation.
2- Surface Condition
Before welding, you must check that the surface of the aluminum is cleaned. It should not contain any impurities. Usually, the aluminum surface gets layers of oxide. Remove and clean the whole surface if you notice any of such layers.
If you don’t clean the surface and weld on the layer of oxide, then the welds will be fragile. Eventually, such weak laser welds will break. Weldings on unclean surfaces can also result in porosity and cracking. Therefore, I recommend you use a wire brush and clean the entire aluminum surface before welding it.
3- Heat Dissipation
One of the biggest hindrances in welding aluminum material is the high reflectivity and thermal conductivity. The heat that lasers provide to aluminum during welding can dissipate due to higher aluminum conductivity levels.
To overcome this issue of heat dissipation, you will have to provide higher energy and a very focused laser beat. The powerful and effective laser will help achieve adequate melting and solidification (when the metals fuse).
The heat will dissipate from the weld pool if the laser beam is not robust. If this happens, the weld on aluminum will be weakened. To avoid this issue, a consistent, powerful laser beam must be applied to fuse material with an aluminum surface. The constant beams won’t allow the heat to dissipate.
How Thick of Aluminum Can a Laser Welder Weld?
It depends on multiple factors, and the laser type is a crucial determinant. If the laser type is powerful, it can weld up to 15mm thickness or even more than that. However, the quality of the weld will decrease when the thickness of the aluminum material increases.
The reason is that while welding the thick piece of aluminum, some heat (provided by the laser beam) will dissipate. Due to this, the pores will be produced in the welds. Those pores will get more significant over time and cause issues.
Conclusion
Aluminum welding is a complex task, even with laser welding. It takes time, energy, and years of experience. If a newbie starts welding aluminum, chances are high that he won’t be able to get a strong weld. The aluminum material can even break.
However, one can weld aluminum using lasers with the proper skillset, dedication, and patience. If done correctly, laser welding will last for years and not break. However, make sure to clean the area before starting weldings.
