Application of laser cutting technology in processing special-shaped parts

2025-10-24

Laser cutting technology primarily uses a focusing lens to focus a CO2 laser beam on the surface of a material, melting it. At the same time, compressed gas coaxial with the laser beam is applied to blow away the melted material, allowing the laser beam and the material to move relative to each other along a specific trajectory, thus forming a slit. With the advancement of science and technology, laser technology has developed rapidly. This technology features high cutting accuracy, fast cutting speed, and is unaffected by shape, with no deformation or burrs in the slit. For this reason, this technology has been widely used in the field of mechanical processing.

1. Advantages of laser cutting technology

(1) High precision: The positioning accuracy of laser cutting technology is 0.05mm, and the accuracy after repeated positioning can reach 0.02mm.

(2) After the laser beam is focused, a very small light spot is formed, and the power density at the intersection is very high, which can quickly heat the material to the vaporization level, forming a hole after evaporation. The beam and the material move relative to each other in a linear manner, forming continuous holes, thereby forming a very small slit. Under normal circumstances, the incision width is 0.10 to 0.20 mm.

(3) The cutting surface is relatively smooth: there are no burrs on the cross section after cutting, and the roughness of the cut surface can usually be controlled within Ra12.5.

(4) Faster speed: The cutting speed can reach 10m per minute, and the maximum positioning speed can reach 70m/min, which is much higher than wire cutting.

(5) Good cutting quality: non-contact cutting can be achieved, the influence of heat on the cutting edge is very small, there has been no problem of workpiece deformation due to heat, so that the material does not collapse during punching and shearing, and usually the cutting seam does not require secondary processing.

(6) The hardness of the material will not affect the use of cutting technology: Laser cutting technology can be used to complete the processing of stainless steel, carbide, steel plates and aluminum alloy plates. Regardless of the hardness of the material, it can ensure that there will be no deformation problems during cutting.

(7) It can effectively save investment in molds: Unlike other types of parts processing, laser processing technology does not require suitable molds, and there is no problem of mold wear and mold repair. It can reduce the time for mold replacement during processing, save processing costs, and achieve effective control of production costs. It has great advantages in processing larger products.

2 .Specific measures for processing special-shaped parts

Combined with the material, parameters and geometric contours of special-shaped materials, the processing procedures and process parameters of laser cutting technology are reasonably selected, and appropriate processing methods are selected to effectively eliminate the processing defects of parts and ensure the quality of part processing.

2.1 Interval point method

If the length and width of plate parts are relatively large, the parts will deform as the thickness and ratio of the workpiece change. Figure 1 is a schematic diagram of cutting defects. For this defect, the material of the plate should be considered and the cutting method should be selected. If the part is made of carbon steel plate and is later painted or treated with other chemical processes, the requirements for cutting roughness are not very high, and the micro-welding function of the laser cutting machine itself can be used for processing. Click the relevant function button in the processing program interface to complete the creation of micro-weld points. If the part material is stainless steel, such parts generally have high requirements for appearance. If micro-welding is used for cutting, welding marks are likely to be generated, and these marks are not easy to eliminate, which will have a certain impact on the appearance of the part. For parts of this material, the interval point cutting method can be used for cutting, and the interval points need to be created through the operating program. When there are differences in the thickness T value of the material, the spacing needs to be appropriately adjusted to ensure that the two workpieces are easy to separate after cutting and will not affect the cutting surface. After testing, it was found that when the thickness value T≤1.5mm, the spacing value δ=1mm, and when 2mm≤T≤4mm, the spacing value δ=0.5mm.

The spacing point cutting method is more applicable in the processing of symmetrical parts and can be promoted accordingly.

2.2 Transition lead method

Since the size of the parts themselves is relatively small, the cutting speed is relatively fast. The temperature of the starting point has not completely cooled down, and repeated cutting is required to complete the arc closing process, resulting in serious burning problems at the starting and end points of the cutting. The contour after cutting cannot reach the standard size, and the roughness of the cut surface seriously exceeds the standard. After testing, the transition method is adopted to merge single parts and cut multiple workpieces at one time. The starting and end points of the cutting are introduced into the cutting waste area to avoid overlap of the starting and end points of the cutting, thereby effectively avoiding burn-in defects in the workpiece cutting.

2.3 Three-dimensional cutting method

Cold-bent special-shaped steel pipes have the characteristics of high strength and light weight. The use of this workpiece can simplify the welding process and deformation assembly problems, save the labor required for structural installation, and improve the performance of the product. Therefore, this workpiece is also widely used. However, due to the large variety of special-shaped steel pipes, complex shapes, and three-dimensional geometric shapes, there are great differences in the length of the finished products, which leads to great difficulties in the design and processing of this workpiece.

After long-term research on the design platform of relevant software and PEPS Pentacut 3D laser cutting technology, it was found that the positioning plate for making cutting fixtures can effectively improve the efficiency and quality of workpiece positioning cutting. The main idea of cutting is to transform the traditional three-dimensional workpiece cutting in the form of spatial curved surfaces into a simpler two-dimensional cutting. This can effectively reduce the workload of fine processing, thereby shortening the time for manufacturing tooling and fixtures, making it easier to meet the cutting accuracy. Moreover, the use of three-dimensional cutting method for two-dimensional plate blanking is simpler and faster than three-dimensional workpiece processing, which can effectively control the production time and production cost of mounting brackets and fixtures.

3 Conclusion

To sum up, laser cutting technology has many advantages in parts processing, including high precision, small kerf, fast speed, material saving, good cutting quality, no influence from material factors, cost saving, and conducive to the production of new products. However, there are still some defects when using laser cutting technology to process special-shaped parts. The main reason is the lack of rationality in the use of laser cutting technology. When processing special-shaped parts, it is necessary to master the characteristics of the parts and laser cutting technology, clarify the physical properties, shape, material, processing requirements, etc. of the parts, and make a reasonable choice of cutting method to avoid improper use of cutting technology, which may cause burns, deformation, melt marks or excessive roughness on the parts, affecting the processing quality of special-shaped parts.