Core Principle Differences: Different Energy Mechanisms
1. Laser Welding: Primarily based on heat conduction. The laser beam (power density typically 10^4~10^6 W/cm²) locally melts the material to form a molten pool, which is then joined upon cooling. Commonly used in automotive manufacturing for lap welding of 1.5mm thick steel plates (reference: *Chinese Journal of Lasers*, 2023).
2. Laser Cutting: Uses high energy density (10^6~10^8 W/cm²) to instantly vaporize or melt the material, with auxiliary gases such as oxygen/nitrogen used to remove slag. For example, cutting 6mm stainless steel requires a peak power ≥2kW (International Institute of Welding (IIW) standard).
Process Parameter Comparison: Key Value Differentiation
1. Power Range:
Welding: Low to medium power (500W-6kW), 1-3kW is commonly used for thin plate welding.
Cutting: Medium to high power (1kW-20kW), ≥1.5kW is required for 6mm carbon steel.
2. Spot Diameter:
Welding: Larger (0.2-1mm), promoting molten pool stability.
Cutting: Smaller (0.05-0.3mm), improving energy concentration.
Equipment Configuration Differences: Different Functional Components
1. Welding Head: Equipped with an oscillating module (e.g., galvanometer) to achieve complex trajectory welding, with protective gas (argon) to prevent oxidation.
2. Cutting Head: Built-in nozzle (1-3mm orifice) controls the auxiliary gas flow direction, and a capacitive height sensor ensures a constant focal position.
Typical Application Scenarios
1. Welding Applications:
Precision electronic components (e.g., battery tab welding, thickness 0.1mm).
Aerospace titanium alloy structural parts (depth-to-width ratio > 5:1).
2. Cutting Advantage Scenarios:
- Metal sheet blanking (e.g., automotive door panel cutting, tolerance ±0.1mm).
- Complex contour processing (fiber laser cutting speed up to 30m/min, data source: Laser Institute of America (LIA)).
How to Quickly Select a Process?
Preliminary judgment based on material thickness:
<3mm and requires connection: Welding is preferred.
>1mm and requires separation: Cutting is the preferred method.
Special Case: Perforation cutting (such as pipe drilling) requires pulsed laser, and the parameters are completely different from continuous laser welding.
