Laser cutting machines and laser welding machines both use lasers for metal processing, but they are designed for different purposes. This article explains their working principles, main functions and application differences, helping you choose the right laser equipment for cutting or welding tasks.
Laser Cutting vs. Laser Welding: Understanding the Differences in Metal Processing
Laser cutting machines and laser welding machines both rely on lasers to complete metal processing tasks. Their working principles are similar, but their processing objectives are different. This article briefly introduces the differences between the two types of laser equipment.
How Does a Laser Cutting Machine Work?
A laser cutting machine emits a horizontal laser beam from the laser tube. The beam is then reflected by a 45° full reflector and directed vertically downward. After being focused by a lens, the laser beam forms a very small spot at the focal point.
At the spot, the laser power density can reach approximately 10⁶ to 10⁹ W/cm². When the workpiece at the focal point is irradiated by this high-power-density laser spot, the local temperature rises instantly above 10,000°C, causing the material to vaporize rapidly.
With the assistance of cutting gas, the vaporized metal is blown away, forming a small hole in the workpiece. As the CNC machine tool moves, countless small holes are connected to form the desired cutting shape.
Due to the high frequency of laser cutting, the joints between each small hole are very smooth. As a result, the cut product usually has a high surface finish.
How Does a Laser Welding Machine Work?
A laser welding machine is a new type of welding equipment, mainly used for thin-wall materials and precision component welding. It can complete spot welding, butt welding, lap welding, seal welding and other welding processes.
Compared with traditional welding methods, laser welding has the following characteristics:
- High depth-to-width ratio
- Narrow weld seam
- Small heat-affected zone
- Small deformation
- Fast welding speed
- Flat and beautiful weld appearance
- Little or no post-welding treatment required
- Stable weld quality
- Low porosity
- Precise control
- Small focused spot
- High positioning accuracy
- Easy to achieve automation
Laser welding uses high-energy laser pulses to heat a local area of the material. The laser energy is transmitted into the material through heat conduction, causing the material to melt and form a specific molten pool.
What Is the Main Difference Between Them?
The principle of laser welding is similar to that of laser cutting, but the processing purpose is opposite. The core difference mainly lies in how the laser energy is controlled and used.
Laser cutting focuses on vaporizing or melting the material to separate it into the required shape. Laser welding focuses on melting the material locally so that different parts can be joined together after solidification.
In some cases, both processes can even be completed on the same machine, with differences in the control program, laser power setting and processing parameters.
Final Suggestion
Laser cutting and laser welding are both important applications of laser technology in metal processing. When selecting equipment, it is necessary to clarify whether the main requirement is material separation or material joining, so as to choose the most suitable laser processing method.
