Fiber Laser Welding Machine Welding on Different Kinds of Steel Raw Material

Fiber laser welding machines are highly versatile and effective for welding various types of steel due to their high precision, speed, and ability to produce deep, narrow welds with minimal heat-affected zones (HAZ). Here are how fiber laser welding performs on different kinds of steel raw materials:

1. Carbon Steel (Low & Medium Carbon)

• Weldability: Excellent

• Key Considerations:

• Low carbon steel (e.g., AISI 1018) welds easily with minimal cracking risk.

• Medium carbon steel (e.g., AISI 1045) requires controlled heat input to avoid brittleness in the HAZ.

• Preheating may be needed for high-carbon steels to prevent cracking.

• Laser Parameters: Moderate power (1-4 kW), high speed, and shielding gas (Argon or Nitrogen).

2. Stainless Steel (Austenitic, Martensitic, Ferritic)

• Weldability: Very Good (with proper settings)

• Key Considerations:

• Austenitic (304, 316): Resistant to cracking; may require low heat input to avoid carbide precipitation.

• Martensitic (410, 420): Prone to cracking; preheating and post-weld heat treatment (PWHT) may be needed.

• Ferritic (430): Can develop brittleness; low heat input and fast cooling help.

• Laser Parameters: High power (2-6 kW), pulsed or continuous wave (CW) mode, and inert gas shielding.

3. Tool Steel & High-Speed Steel (HSS)

• Weldability: Moderate to Difficult

• Key Considerations:

• High hardness and carbon content increase cracking risk.

• Preheating and PWHT are often necessary.

• Low heat input and precise control are critical.

• Laser Parameters: Pulsed laser mode, lower power (to reduce stress), and slow cooling.

4. Galvanized Steel (Zinc-Coated)

• Weldability: Challenging

• Key Considerations:

• Zinc vaporization can cause porosity and spatter.

• Requires gap or ventilation to allow zinc gas escape.

• High-speed welding reduces zinc boiling effects.

• Laser Parameters: High speed, moderate power, and proper joint design (e.g., lap joints with gaps).

5. High-Strength Low-Alloy (HSLA) Steel

• Weldability: Good

• Key Considerations:

• Designed for welding but requires controlled heat input.

• Minimal preheating needed compared to tool steels.

• Laser Parameters: Medium power (2-5 kW), optimized beam focus, and shielding gas.

6. Duplex & Super Duplex Stainless Steel

• Weldability: Good (with care)

• Key Considerations:

• Balanced ferrite-austenite phase must be maintained.

• Excessive heat can lead to sigma phase formation (embrittlement).

• Laser Parameters: Controlled heat input, shielding gas (N₂ mix for austenite retention).

General Advantages of Fiber Laser Welding for Steel:

• High Precision: Ideal for thin sheets and intricate welds.

• Low Distortion: Minimal HAZ reduces warping.

• Deep Penetration: Keyhole welding allows thick-section welding.

• Automation-Friendly: Easily integrated into robotic systems.

Challenges & Solutions:

• Reflectivity: Some steels (e.g., stainless) reflect laser light; anti-reflective coatings or higher power can help.

• Cracking: Controlled cooling and filler wire (if needed) reduce cracking in hardenable steels.

• Porosity: Proper gas shielding and joint preparation minimize defects.