How to use a fiber laser to cut an aluminum sheet?

Cutting aluminum with precision used to be a pain. Burrs, rough edges, slow speeds—you name it. I’ve seen manufacturers spend hours fixing cuts that should have been clean from the start. Luckily, fiber lasers changed the game.

Yes, you can cut aluminum cleanly and efficiently with the right fiber laser—especially if you know the right settings and machine power to use.

Many people still wonder if fiber lasers are right for aluminum. I used to think the same. But after working with clients who switched from CO₂ to fiber lasers, the results spoke for themselves. In this article, I’ll explain what makes aluminum tricky, what laser power works best, and how to get the cleanest cuts possible.

Can you cut aluminum with a fiber laser?

Rough edges, slow cutting, and high reflectivity make people think aluminum can't be laser cut. But that’s not true—at least not with the right machine. I've had clients come to me frustrated after trying CO₂ machines on aluminum with poor results.

Yes, fiber lasers can cut aluminum—cleanly, efficiently, and with minimal post-processing—if you use the right power and settings.

Why fiber lasers work better for aluminum

CO₂ lasers¹ often struggle with aluminum because of its high reflectivity. The beam bounces, causing poor absorption and heat buildup in all the wrong places. That means slow speeds, rough edges, and wasted time. But fiber lasers have a shorter wavelength—usually 1064nm—which aluminum absorbs better. That means faster cutting, better precision, and less burr.

Real client example

One of my clients in Europe was cutting 3mm aluminum with a CO₂ laser. The edges were rough and blackened. They needed to grind and polish every single sheet. After switching to our Kirin Laser fiber cutting machine, they got clean cuts, no more grinding, and production time dropped by 40%.

Laser Type	Cut Quality	Cutting Speed	Maintenance	Power Efficiency
CO₂	Rough	Slow	High	Low
Fiber	Clean	Fast	Low	High

The key is using the right setup. If you cut aluminum regularly, fiber lasers² are the only real option. CO₂ might seem cheaper up front, but the downtime and rework add up quickly.

What settings should I use to laser cut aluminum?

Even with the best machine, bad settings can ruin your results. I’ve worked with dozens of manufacturers who didn’t realize how much the wrong settings held them back.

To laser cut aluminum, you need high power, fast speed, and assist gas—usually nitrogen—for clean, burr-free results.

Start with power and speed

For thin sheets like 1-2mm, 1.5kW–3kW fiber lasers³ work well. For 3-6mm sheets, I recommend at least 3kW. Once you’re cutting 8mm or more, go with 6kW or higher. Aluminum conducts heat quickly, so you need power to stay ahead of it.

Aluminum Thickness	Recommended Power	Cutting Speed (mm/min)	Gas Type
1-2mm	1.5kW–3kW	3000–5000	Nitrogen
3-6mm	3kW–6kW	1500–2500	Nitrogen
8-15mm	6kW–12kW	1000–2000	Nitrogen

Use nitrogen, not oxygen

Oxygen reacts with aluminum and leaves a dirty, oxidized edge. Nitrogen keeps the cut clean and shiny. Yes, it costs more, but you save time on cleanup. Trust me—every client who switched to nitrogen⁴ thanked me later.

Focus and nozzle matters too

You also need a small nozzle and tight focus. The laser spot should be as small as possible to get a narrow kerf and smooth edge. At Kirin Laser, we pre-configure focus systems for aluminum to make setup easier for our clients.

How powerful of a laser is needed to cut aluminum?

This is one of the first questions buyers ask me. Many people think they can get by with a 1kW or 2kW machine—but for aluminum, that’s rarely enough.

To cut aluminum efficiently, use at least 3kW for sheets under 6mm, and 6kW or more for thicker cuts. Power equals speed and edge quality.

The truth about power

Low-power lasers can technically cut thin aluminum. But that doesn't mean they do it well. You get slow speeds, poor edge quality, and more dross. I’ve had clients try 1.5kW lasers on 4mm aluminum⁵. They spent more time cleaning the parts than cutting them.

Why higher power matters

Fiber lasers don’t just burn through the material. They melt and blow it away with assist gas. So if your power is too low, the aluminum absorbs heat, but not enough to maintain clean vaporization. That causes micro-burrs, messy edges, and even back reflections.

My recommendation

At Kirin Laser, our 6kW and 12kW models cut aluminum⁶ up to 15mm with ease. If you’re doing volume production, it pays off fast. Cleaner edges mean no sanding. Faster speed means more output per shift.

Power Level	Max Aluminum Thickness	Edge Quality	Use Case
1kW	1–2mm	Fair	Hobby, Prototyping
3kW	4–6mm	Good	Small Job Shops
6kW	8–12mm	Excellent	Production, OEM
12kW	15mm+	Excellent	High-Speed Manufacturing

If you're in the aluminum business, don’t settle for low-power machines⁷. You’ll waste time and money trying to fix bad cuts.

Why is aluminum hard to laser cut?

Aluminum is light, durable, and widely used—but it’s not the easiest material to laser cut. Many of my first-time clients are surprised by the challenges they face.

Aluminum is hard to laser cut because it's reflective, conductive, and forms burrs easily. Without the right laser and gas, cuts can be messy and slow.

Three main reasons aluminum causes trouble

1. High reflectivity

Aluminum reflects a lot of laser energy, especially at CO₂ wavelengths. This can bounce energy back into the optics or cause poor absorption. Fiber lasers⁸ reduce this risk because they operate at a shorter wavelength that aluminum absorbs better.

2. Thermal conductivity

Aluminum pulls heat away from the cutting area quickly. That makes it harder to maintain the melt pool unless your laser has enough power. This also causes the material to heat up unevenly, creating warping or rough cuts.

3. Burr formation

Unlike steel, aluminum tends to form burrs when the melt isn't fully ejected. Without the right gas pressure and cutting speed⁹, you end up with edges that need extra finishing.

Challenge	Effect on Cutting	How Fiber Laser Helps
Reflectivity	Scattered beam, poor penetration	Better absorption with 1064nm light
Heat conduction	Melts unevenly, warps	High power compensates
Burrs	Needs post-processing	High-speed clean cuts with nitrogen

This is why aluminum demands better machines and smarter settings. You can’t just use default parameters. I help my customers fine-tune their systems to cut clean every time.

Conclusion

Fiber lasers make cutting aluminum¹⁰ faster, cleaner, and easier—if you use the right machine, settings, and gas. At Kirin Laser, we’ve helped clients around the world switch from CO₂ to fiber systems with incredible results. Whether you're cutting 2mm or 15mm sheets, getting it right means faster production, better quality, and fewer headaches. If you’re serious about aluminum, fiber is the only way to go.