Compared to other thermal cutting methods, laser cutting is characterized by its high speed and high quality. Specifically, this can be summarized in the following aspects:
(1) High Cutting Quality
Due to the small laser spot size, high energy density, and high cutting speed, laser cutting achieves excellent cutting quality.
① Laser cutting produces narrow kerfs with parallel sides perpendicular to the surface, achieving a dimensional accuracy of ±0.05mm for cut parts.
② The cut surface is smooth and aesthetically pleasing, with a surface roughness of only tens of micrometers. Laser cutting can even be used as the final step, eliminating the need for machining, allowing for direct use of the parts.
③ After laser cutting, the heat-affected zone is very small, and the material properties near the kerf are almost unaffected. Workpiece deformation is minimal, cutting precision is high, and the kerf geometry is excellent, with a relatively regular rectangular cross-section. A comparison of laser cutting, oxyacetylene cutting, and plasma cutting methods is shown in Table 1, using 6.2mm thick low-carbon steel plates as the cutting material.
(2) High Cutting Efficiency: Due to the transmission characteristics of laser light, laser cutting machines are generally equipped with multiple CNC worktables, allowing for fully CNC-controlled cutting throughout the entire process. During operation, simply changing the CNC program allows for cutting parts of different shapes, enabling both two-dimensional and three-dimensional cutting.
(3) High Cutting Speed: A 1200W laser can cut 2mm thick low-carbon steel plates at speeds up to 600cm/min; cutting 5mm thick polypropylene resin sheets can reach speeds of up to 1200cm/min. Materials do not require clamping or fixing during laser cutting, saving on tooling and fixtures, as well as auxiliary time for loading and unloading.
(4) Non-Contact Cutting: During laser cutting, the torch and workpiece do not contact each other, eliminating tool wear. Processing parts of different shapes does not require changing the "tool," only adjusting the laser's output parameters. The laser cutting process is low-noise, low-vibration, and pollution-free.
(5) Wide Range of Cutting Materials
Compared to oxyacetylene cutting and plasma cutting, laser cutting can cut a wider range of materials, including metals, non-metals, metal-based and non-metal-based composites, leather, wood, and fibers. However, different materials exhibit varying degrees of adaptability to laser cutting due to their different thermophysical properties and laser absorption rates. Table 2 shows the laser cutting performance of various materials using a CO2 laser.
(6) Disadvantages
Due to limitations in laser power and equipment size, laser cutting can only cut medium to thin-thickness plates and pipes. Furthermore, the cutting speed decreases significantly with increasing workpiece thickness.
Laser cutting equipment is expensive, requiring a large initial investment.
