Épaisseur de coupe laser à fibre : quelle épaisseur un laser à fibre peut-il couper ?

It is important to understand the thickness of fiber laser cutting during the selection of laser source in metal fabrication. The cutting ability is mainly dependent on the laser power, type of material and process parameters. Extremely thin systems are produced using high-power systems, although the maximum possible thickness in practice frequently varies compared to the theoretical maximum.

According to jsragos’s published specifications, modern fiber lasers can cut carbon steel up to 100 mm at 40 kW, while lower-power systems handle thinner ranges proportionally .

This guide breaks down thickness ranges by power level and explains what really affects performance in real-world applications.

Comment la puissance du laser affecte l’épaisseur de coupe

Laser power (measured in watts or kilowatts) directly influences how much material the beam can melt and eject along the cut line.

jsragos’s published data shows the following maximum thickness capabilities across power levels :

500W Fiber Laser

• Carbon steel: up to 6 mm

• Stainless steel: up to 3 mm

• Aluminum: up to 2 mm

• Copper: up to 2 mm

2000W Fiber Laser

• Carbon steel: up to 20 mm

• Stainless steel: up to 8 mm

• Aluminum: up to 6 mm

• Copper: up to 4 mm

6000W Fiber Laser

• Carbon steel: up to 25 mm

• Stainless steel: up to 20 mm

• Aluminum: up to 15 mm

• Copper: up to 8 mm

12000W Fiber Laser

• Carbon steel: up to 40 mm

• Stainless steel: up to 30 mm

• Aluminum: up to 30 mm

40000W Fiber Laser

• Carbon steel: up to 100 mm

• Stainless steel: up to 80 mm

• Aluminum: up to 70 mm

• Copper: up to 40 mm

These figures represent maximum achievable thickness under optimized conditions.

Production réelle vs épaisseur maximale

Although published specifications may indicate certain maximums, practical shop-floor performance often varies.

For example, a Reddit user operating a 2000W fiber laser reported reliable cutting of 18 mm mild steel and 6 mm stainless steel in production .

Another user noted difficulty achieving clean cuts on thicker stainless steel using a 3 kW machine, especially at 10 mm thickness .

These examples highlight an important point:

Maximum thickness ≠ optimal production thickness.

In most fabrication environments, operators run below the maximum rating to maintain cut quality, speed, and edge consistency.

Le type de matériau compte

Different materials respond differently due to reflectivity, thermal conductivity, and melting characteristics.

Acier au carbone

Often achieves the highest cutting thickness due to favorable absorption and compatibility with oxygen assist gas .

Acier inoxydable

Typically cut with nitrogen for clean edges, but requires more power than carbon steel at equivalent thickness .

Aluminium

Reflective and thermally conductive, yet fiber lasers perform well due to their wavelength (around 1.06 microns), which improves metal absorption .

Copper & Brass

Highly reflective; thickness capacity is usually lower than steel at the same wattage .

Facteurs clés qui influencent l’épaisseur maximale de coupe

Beyond power level, several technical factors affect how thick a fiber laser can cut:

1. Beam Quality (BPP)

Better beam quality allows tighter focusing, increasing energy density and penetration .

2. Focus Position & Lens Quality

Proper focus placement is critical for thicker material cutting. Incorrect focus can degrade bottom-edge quality .

3. Assist Gas Selection

• L’oxygène améliore la vitesse de coupe dans l’acier au carbone

• L’azote produit des bords en acier inoxydable propres

• Les impacts sur la pureté du gaz réduisent la consistance

4. Cutting Speed

Slower speeds allow deeper penetration but may affect productivity .

5. Nozzle Diameter

Smaller nozzles can improve energy concentration for thin sheets; larger nozzles assist thicker sections .

Estimation de l’épaisseur de coupe par puissance

jsragos outlines a simplified conceptual relationship:

T = k × Pⁿ

Where:

• T = épaisseur maximale

• P = puissance laser

• k et n = constantes spécifiques au matériau

This model shows that thickness increases as power rises—but not in a perfectly linear way.

Laser à fibre vs Autres types de lasers

jsragos also compares fiber lasers to CO₂ and Nd lasers:

• Les lasers à fibre surpassent généralement le CO₂ lors de la coupe de métaux réfléchissants comme l’aluminium

• Les lasers à fibre atteignent généralement une épaisseur d’acier inoxydable supérieure à celle des systèmes Nd à puissance équivalente

Because fiber lasers operate around 1.06 µm wavelength, metals absorb energy efficiently, improving penetration depth .

Recommandations pratiques pour les fabricants

If you are selecting a fiber laser for metal fabrication:

• 500W–1000W → Thin sheet metal (≤6 mm mild steel)

• 2000W–3000W → Medium fabrication (≤20 mm carbon steel under ideal conditions)

• 6000W+ → Heavy industrial work (≥25 mm steel)

• 12000W+ → Thick plate and structural applications

For consistent industrial production, consider operating at 70–80% of the rated maximum thickness to maintain edge quality and cutting speed stability.

Conclusion à retenir

Fiber laser cutting thickness depends on:

• Puissance laser

• Type de matériau

• Qualité du faisceau

• Précision de la mise au point

• Assistance au choix des gaz

• Vitesse de coupe

While ultra-high-power systems can reach 100 mm carbon steel under optimized conditions , practical fabrication performance should prioritize stability, speed, and edge quality rather than pushing absolute limits.