Laser Cutting Steel: Techniques and Best Practices

Cutting steel sounds like a job for the tough and mighty, right? But what if I told you that a focused beam of light can slice through steel like butter? As a sales engineer at Kirin Laser, I’ve seen firsthand how laser cutting technology has revolutionized the metal fabrication industry. Whether you’re working on intricate designs or large industrial projects, laser cutting is the secret weapon you need. But, how does it work? And how do you get the best results? Let’s dive in.

Hot-selling Laser Cutting Machine

Why Laser Cutting Steel?

The advantages of laser cutting steel are too good to ignore. Traditional cutting methods involve physical contact, which wears down tools over time and creates uneven cuts. Laser cutting, on the other hand, is contactless. It offers cleaner edges, higher precision, and faster turnaround times. But that’s not all—it works on a variety of steel types and thicknesses, making it versatile and efficient.

Laser cutting outshines traditional methods by offering precision, speed, and versatility—three essential factors for modern fabrication shops. If you’re cutting steel regularly, you’ll see the payoff quickly in reduced labor costs and better-quality products.

How Does Laser Cutting Work?

When you send steel under the beam, the magic happens! The laser beam—either from a fiber or CO2 source—focuses intense light energy on a small area, melting or vaporizing the steel. The precision of this process is controlled by CAD files, which guide the laser across the material with incredible accuracy. Whether you’re cutting stainless steel or carbon steel, the process remains the same—only the laser’s power and cutting speed need adjusting.

If you’re wondering, “Do I need fiber or CO2 lasers for my project?” The answer depends on the type of steel you’re working with. Fiber lasers are more energy-efficient and better for cutting thinner metals like stainless steel.

What Are the Best Practices for Laser Cutting Steel?

I always tell my clients, “Get your settings right, and half the battle is won.” Laser power, speed, and gas pressure need to be tailored to the type of steel you’re cutting. For example, when cutting stainless steel, nitrogen is often the preferred assist gas, as it creates a clean, oxidation-free edge. For carbon steel, however, oxygen might be used to achieve faster cutting speeds, though it can leave some oxidation marks.

Knowing which gas to use and when makes a huge difference in the final product quality. One of my go-to best practices is using nitrogen for a shiny finish on thinner stainless steel sheets, while oxygen is perfect for thicker carbon steel when speed is crucial. In the below, there is a 3kw laser cutting deta sheet for your references. It has a very specific explain about how to use the assistant gas.

Steel Thickness and Laser Cutting: What Should You Know?

Not all steel is created equal. Some projects require you to cut steel as thin as 1 mm, while others need 20 mm plates sliced down. Here’s where things get interesting. The thicker the steel, the more powerful the laser you need. But there’s a catch—too much power can overheat and deform the steel, while too little power results in incomplete cuts.

In my experience, adjusting laser power and speed based on thickness is key. A 3kW fiber laser might be perfect for cutting up to 10 mm of stainless steel, while thicker materials will require a more powerful 6kW laser.

Data of 3KW Laser Cutting Sheet

Carbon steel Q235B cutting parameters

• 1) The optical ratio is 100/150 (collimation/focusing lens focal length)
• 2) Cutting auxiliary gas: liquid oxygen (purity 99.5%) liquid nitrogen (purity 99.99%)

Material	Thickness mm	Gas	Speed m/min	Power (W)	Pressure bar	Nozzle	Cutting Height mm	Focus mm
CS Q235B	1	N2	55.0-60.0	3000	12-16	1.5 Single	0.5	0
	2	N2	15.0-17.0	3000	12-16	1.5 Single	0.5	0
	3	O2	4.1-4.5	3000	0.6-0.8	1.0-1.2 Double	0.6	5.5
	4	O2	3.0-4.0	3000	0.6-0.8	1.0-1.2 Double	0.6	6.6
	6	O2	2.6-2.9	3000	0.6-0.8	1.0-1.2 Double	0.6	4.5
	8	O2	2.1-2.3	3000	0.6-0.8	1.0-1.2 Double	0.6	5.2
	10	O2	1.3-1.6	3000	0.5-0.7	3.5-4.0 Double	0.6	5.5
	12	O2	1.0-1.4	3000	0.5-0.7	3.5-4.0 Double	0.8	3.4
	14	O2	0.9-1.2	3000	0.5-0.7	3.5-4.0 Double	0.6	3.6
	16	O2	0.8-1.0	3000	0.5-0.7	4.5-6.0 Double	0.5	4.7
	18	O2	0.7-0.9	3000	0.5-0.7	4.5-6.0 Double	0.8	4.7
	20	O2	0.6-0.8	3000	0.5-0.7	4.5-6.0 Double	1	5.2

Stainless steel SUS304 cutting parameters

• 1) The optical ratio is 100/150 (collimation/focusing lens focal length)
• 2) Cutting auxiliary gas: liquid nitrogen (purity 99.99%)      

Material	Thickness mm	Gas	Speed m/min	Power (W)	Pressure bar	Nozzle	Cutting Height mm	Focus mm
SS (SUS304)	1	N2	45.0-50.0	3000	10-12	1.5-2.0 Single	1	0
	2	N2	25.0-27.0	3000	10-12	1.5-2.0 Single	0.8	0
	3	N2	8.0-10.0	3000	10-12	1.5-2.0 Single	0.5	-1
	4	N2	5.0-6.5	3000	12-16	2.5-3.0 Single	0.5	-2.3
	6	N2	2.0-3.0	3000	12-16	3.0-3.5 Single	0.5	-4.8
	8	N2	1.2-1.5	3000	15-18	3.5-4.0 Single	0.5	-5.8
	10	N2	0.6-0.7	3000	15-18	4.5-5.0 Single	0.5	-8.8
	12	N2	0.45-0.55	3000	18-21	4.5-5.0 Single	0.1	-11.4

Aluminum alloy cutting parameters

• 1) The optical ratio is 100/150 (collimation/focusing lens focal length)
• 2) Cutting auxiliary gas: air (20% oxygen + 80% nitrogen)

Material	Thickness mm	Gas	Speed m/min	Power (W)	Pressure bar	Nozzle	Cutting Height mm	Focus mm
AL	1	Air	33.0-37.0	3000	10-14	1.5-2.0 Single	0.8	0
	2	Air	19.0-22.0	3000	10-14	1.5-2.0 Single	0.8	0
	4	Air	5.0-6.0	3000	10-14	1.5-2.0 Single	0.5	-3.1
	6	Air	2.0-2.5	3000	12-16	3.0-3.5 Single	0.5	-3.8
	8	Air	1.0-1.4	3000	15-18	3.5-4.0 Single	0.5	-3.8
	10	Air	0.5-0.7	3000	15-18	4.5-5.0 Single	0.5	-6.3

 Brass cutting parameters

• 1) The optical ratio is 100/150 (collimation/focusing lens focal length)
• 2) Cutting auxiliary gas: liquid nitrogen (purity 99.99%)

Material	Thickness mm	Gas	Speed m/min	Power (W)	Pressure bar	Nozzle	Cutting Height mm	Focus mm
brass	1	N2	28.0-30.0	3000	10-14	1.5-2.0 Single	0.8	0
	2	N2	15.0-18.0	3000	10-14	1.5-2.0 Single	0.8	0
	3	N2	7.0-10.0	3000	10-14	1.5-2.0 Single	0.5	-0.5
	4	N2	4.0-6.0	3000	15-18	2.5-3.0 Single	0.5	-0.8
	6	N2	1.0-1.8	3000	15-18	3.5-4.0 Single	0.5	-2
	8	N2	0.75-0.9	3000	15-18	3.5-4.0 Single	0.5	-6.8

What Type of Steel Can You Cut?

Laser cutting isn’t just for one type of steel—it’s a jack-of-all-trades in the metal world. Whether you’re dealing with stainless steel, carbon steel, or even alloy steel, the versatility of laser cutting is undeniable. For example, stainless steel offers high corrosion resistance, making it ideal for industries like food processing and healthcare, where hygiene is critical.

On the other hand, carbon steel, known for its strength, is often used in construction and heavy machinery. I often recommend clients to adjust their cutting settings when dealing with carbon steel, as it requires different assist gases and laser parameters compared to stainless steel.

Tips for Avoiding Common Laser Cutting Mistakes

One of the most common mistakes I see—especially for those new to laser cutting—is failing to calibrate the machine regularly. It’s like driving a car with misaligned tires—you might get where you’re going, but you’ll have problems along the way. Regular calibration ensures the laser beam stays focused and accurate, which directly affects the cut quality.

Another pitfall? Ignoring the need for clean lenses and mirrors. Dirty optics can reduce laser power and compromise cut quality. I can’t stress enough the importance of keeping your machine in tip-top shape.

Can Laser Cutting Be Used for Precision Jobs?

If you’ve ever looked at an intricately designed steel piece and thought, “How on earth did they cut that?”—laser cutting is probably the answer. The level of precision you can achieve is astonishing. With the right machine, you can cut designs with tolerances as low as 0.1 mm. Precision cutting is ideal for industries like automotive and aerospace, where every millimeter counts.

I’ve seen laser-cut steel used for everything from delicate jewelry designs to high-precision aerospace components. It’s amazing how versatile this technology can be when handled correctly.

Conclusion

Laser cutting steel isn’t just about slicing through metal—it’s about doing it efficiently, accurately, and without wear and tear on your equipment. With the right settings, machine maintenance, and understanding of materials, laser cutting can be a game-changer for any steel fabrication project.

If you want to learn more about how Kirin Laser’s cutting-edge technology can help you with your next project, don’t hesitate to reach out! Let’s take your steel cutting process to the next level together.