How To Improve The Quality Of Laser Cutting
Many companies use laser cutting machine are very concerned about: how to use laser cutting machine to work out the quality of good workpieces?
Summarize the factors that affect the quality of cutting: cutting speed, focus position, auxiliary gas, laser output power and workpiece characteristics! We will give you one by one to analyze:
1. The effect of cutting speed on cutting quality
For a given laser power density and material, the cutting speed is in accordance with an empirical formula. As long as the threshold is above the threshold, the cutting speed of the material is proportional to the laser power density, that is, increasing the power density can increase the cutting speed. The power density referred to here is related not only to the laser output power but also to the beam quality mode. In addition, the characteristics of the beam focusing system, that is, after focusing the spot size also has a great impact on laser cutting.
2. The effect of focus position adjustment on cutting quality
Since the laser power density has a great influence on the cutting speed, the choice of lens focal length is an important problem.In most applications, the beam focus is adjusted to just under the nozzle. Nozzle and the workpiece surface spacing is generally about 1.5mm.
3. Effect of auxiliary gas pressure on cutting quality
In general, material cutting requires the use of auxiliary gas, the problem is mainly related to the type and pressure of auxiliary gas. Typically, the auxiliary gas is coaxial with the laser beam to protect the lens from contamination and blow away the bottom slag of the cutting zone. For non-metallic materials and parts of metal materials, the use of compressed air or inert gas, the treatment of melting and evaporation materials, while inhibiting excessive cutting of the cutting area.For most metal laser cutting using active gas (as long as O2), the formation of hot metal with the formation of exothermic reaction, this part of the additional heat can increase the cutting speed of one-third to one-half.When the auxiliary gas is oxygen, its purity has a significant effect on the quality of the cutting. A reduction in oxygen purity of 2% reduces the cutting speed by 50% and results in a significant deterioration in the quality of the incision.
4. Effect of laser output power on cutting quality
For the continuous wave output of the laser, the laser power size and mode will have an important impact on the cutting. In practice, often set the higher power to obtain a higher cutting speed, or to cut thick materials. However, the beam pattern (the distribution of beam energy in the cross section) is sometimes more important, and the pattern often changes slightly when the output power is increased.
In summary, although the factors affecting the laser cutting is more complex, but the cutting speed, focal position, auxiliary gas pressure and laser power and mode structure is four very important variables. In the cutting process, if found that the quality of cutting significantly worse, we must first check the factors discussed above and timely control.