With the rapid development of laser technology, the use of fiber lasers is becoming more and more common in the industrial market. For many metal processing projects, choosing the right laser is very important for the final cutting, marking or engraving. This article will tell you how many watts laser should I get for metal cutting, engraving, and welding. I hope it will be helpful to you.
Laser Power and Importance for Metalworking
Laser power (measured in watts) determines the strength of the laser beam. Higher wattage means a more powerful beam, capable of cutting or engraving thicker materials or at a faster rate. When cutting metal, insufficient power results in slow cuts and rough edges, while too much power can cause the material to melt or burn. For engraving, a balance is needed to achieve the desired depth and detail without damaging the material.
What Factors Influence Laser Power Selection?
Material: The type, thickness, and reflectivity of the metal all affect the power required. For example, stainless steel and aluminum are more reflective than carbon steel and require higher power levels.
Task: Cutting, engraving, and welding each have different power requirements. Cutting generally requires higher power than engraving, while welding requires a focused and controlled beam.
Desired results: Factors such as cut quality, engraving depth, and weld strength influence laser power selection.
Material thickness: Thicker materials require higher power levels to penetrate.
Cutting speed: Faster cutting speeds generally require more power.
How Many Watts of Laser Power Do You Need for Metal Cutting, Engraving, and Welding?
Power in laser cutting:
- Aluminum: 750-1000 watts for thin sheets (up to 1mm), 1000-1500 watts for medium thickness (1-5mm), and 1500-3000 watts for thick materials (over 5mm).
- Stainless steel: 500-1000 watts for thin sheets (up to 1mm), 1000-2000 watts for medium thickness (1-5mm), and 2000-4000 watts for thick materials (over 5mm).
Power in laser engraving and marking
When it comes to laser engraving, users will want to understand the power range required for different metals. Generally speaking, for stainless steel and aluminum, 20W to 50W of laser power is usually sufficient, but for harder metals such as titanium or applications that require deeper engraving, lasers over 50W may be required.
Power in welding applications
For welding applications, users may want to understand how high-power lasers (such as 6000W and above) can improve welding efficiency and quality. High-powered lasers can penetrate thicker materials quickly and produce better welds.
Laser Power Wattage for Metal Marking, Engraving or Cutting
Laser Marking
Power range: 20W to 100W.
Principle: The laser beam is focused on the metal surface. After the energy is absorbed by the metal, the temperature of the surface material rises sharply, and it vaporizes after reaching the boiling point, leaving a mark. This process mainly changes the physical state of the surface material. Low power is enough to generate enough heat to achieve this effect.
Application: Suitable for surface marking of metals, alloys, plastics and other materials.
Recommendations:
20W: Suitable for most metal surfaces, enabling clear marking.
30W to 50W: Suitable for applications that require deeper or finer marking, such as electronic components and jewelry.
100W: For highly reflective materials or where fast marking is required.
Laser Engraving
Power range: 25W to 80W.
Principle: The laser energy is concentrated on the metal surface, and after the material reaches the melting point, the molten metal material is blown away by auxiliary gas (such as oxygen and nitrogen), thereby forming an engraved pattern. In this process, low power can control the depth and accuracy of engraving as needed, avoiding problems such as deformation of the metal sheet caused by excessive engraving.
Application: Used for engraving on metal surfaces to create patterns or text.
Recommendations:
25W to 50W: Suitable for shallow engraving, often used for decorative patterns.
80W and above: Used for applications that require deeper engraving or processing harder materials.
Laser Cutting
Power range: 500W to 60000W, depending on material thickness and type.
Principle: High-power laser can provide a large amount of energy to the metal cutting area in a short time, so that thick metal materials can be melted and vaporized quickly. Strong auxiliary gas pressure can effectively blow a large amount of slag and vaporized metal particles away from the cutting area to ensure the continuity and accuracy of cutting. For high-hardness metals, high power can overcome their high melting point and high hardness characteristics and achieve smooth cutting.
Application: Used for cutting metal materials of different thicknesses.
Recommendations:
500W: can cut up to 6mm thick carbon steel and 3mm stainless steel.
1000W: can cut up to 10mm thick carbon steel and 5mm stainless steel.
2000W: can cut up to 16mm thick carbon steel and 8mm stainless steel.
4000W and above: suitable for cutting thicker materials (such as more than 20mm), especially in industries such as automotive manufacturing and aerospace.
How to Choose the Right Laser Power for Engraving Metal
Laser power range
20W to 30W: Suitable for small, intricate markings and shallow engravings, especially on lightweight and coated metals.
30W to 50W: Suitable for medium-depth engraving on metals, capable of fast processing speeds.
50W to 80W: Suitable for applications that require deeper engraving or processing harder materials, such as stainless steel and aluminum.
Laser Marking Power for Engraving Materials
| Material | Recommended Power Range (Watts) |
|---|---|
| Anodized Aluminum | 30 |
| 304 Stainless Steel | 30-80 |
| Aluminum | 50-100 |
| Copper and Brass | 50-100 |
Engraving Depth and Speed
Higher power: more energy is released, deeper engraving is achieved, suitable for complex designs and thicker materials.
Speed
Laser Type and Wavelength
Fiber laser: usually with a wavelength of 1064 nanometers, suitable for metal processing, can provide higher efficiency and better cutting quality.
CO2 laser: although it can also be used for metal, it is less efficient when processing certain metals and is usually used for non-metallic materials.
Other considerations
Material thickness: thicker metal materials require higher power. For example, for metals thicker than 5mm, it is recommended to use a laser of at least 100W.
Application scenario: if it is mainly used for engraving, you should choose a laser device suitable for engraving; if it also involves cutting, you need to consider a higher power device.
How to Choose the Right Laser Power for Welding Metal
Laser power and material thickness
Thin materials (1-2mm): 2-3kW laser power is usually recommended, combined with higher welding speed (5-10 m/min) to avoid overheating and deformation.
Medium-thick materials (4-6mm): 4-6kW laser power is suitable, combined with medium speed (1-3 m/min) to ensure sufficient penetration while controlling the heat-affected zone.
Thick materials (>6mm): 8-10kW laser power is required, combined with lower welding speed (0.5-1 m/min) to ensure sufficient heat transfer and high-strength welds.
Importance of welding speed
Welding speed is closely related to laser power. Increasing welding speed reduces heat input and thus penetration depth. Ideally, laser power and welding speed should be balanced to achieve the best welding effect. For example, when butt welding 6mm stainless steel, about 6kW laser power and a welding speed of 2 m/min are usually required.
Power density and weld quality
Laser power density is an important factor affecting weld formation. Higher power density allows for deeper penetration while reducing the thermal impact on surrounding materials, thus reducing the risk of deformation. It is critical to ensure that the laser beam is well focused to achieve the required power density.
Material type
- Carbon steel: For carbon steel with a thickness of around 10mm, laser powers of more than 6kW are usually required.
- Stainless steel and aluminum: At the same thickness, stainless steel may require higher power to overcome its higher reflectivity and thermal conductivity
How to Choose the Right Laser Power for Cutting Metal
Material Thickness
- Thinner materials require lower power settings and faster cutting speeds.
- Thicker materials necessitate higher power to ensure complete penetration and effective cutting.
Power Settings
| Material | Thickness Range | Recommended Power (Watts) |
|---|---|---|
| Mild Steel | Up to 1mm | 500-750 |
| 1-5mm | 750-1500 | |
| Over 5mm | 1500-4000 | |
| Stainless Steel | Up to 1mm | 500-1000 |
| 1-5mm | 1000-2000 | |
| Over 5mm | 2000-4000 | |
| Aluminum | Up to 1mm | 500-750 |
| 1-5mm | 1000-2000 | |
| Over 5mm | 2000-3000 | |
| Copper | Up to 1mm | 750-1000 |
| 1-5mm | 1000-1500 | |
| Over 5mm | 1500-3000 |
Appropriate Assist Gases
Oxygen assists in cutting mild steel but may cause oxidation.
Nitrogen is often used for stainless steel to minimize oxidation.
Laser Power Guidelines for Different Metalworking Tasks
Cutting:
- Carbon steel and stainless steel: Power requirements increase with material thickness.
- Aluminum: Higher power is needed due to its reflectivity.
- Special alloys: Consult the laser manufacturer for specific recommendations.
Engraving:
- Surface engraving: Lower power is sufficient.
- Deep engraving: Higher power is required.
- Detailed work: A stable beam and precise power control are essential.
Welding:
- Thin materials: Lower power is adequate.
- Thick materials: Higher power is needed to create a deep weld pool.
- Different weld joints: Power requirements vary based on joint design.
Conclusion
Selecting the appropriate laser power for your metalworking project is a critical decision that can significantly impact the quality of your results. By considering the factors discussed above, you can make an informed choice and achieve optimal performance. Consult with a laser equipment specialist to get tailored advice based on your specific needs.
