威廉希尔官方下载Apr 05, 2020
The purpose of the laser cutting machine:
The laser is a kind of coherent light with high intensity, good directivity, and good monochromaticity. Due to the characteristics of small divergence angle and good monochromaticity, the laser can be focused on small spots with the size similar to the wavelength of light (micron or even submicron level) in principle, and the laser itself has high intensity, so the power density at the focus can reach 107 ~ 1011w / cm2, and the temperature can reach more than 10000 ℃. At this high temperature, any material will melt and vaporize rapidly, and spray out explosively at high speed, at the same time, it will produce a strong directional impact. Therefore, laser processing work in the photothermal effect of high-temperature melting and shock wave throw out of the integrated process.
Characteristics of laser processing
The characteristics of laser processing are as follows:
1. Almost all metal and non-metal materials can be laser processed.
2. The laser can focus on a tiny spot, which can be used for micro and precision machining, such as micro narrow slit and micro-hole machining.
3. The laser beam can be sent to the isolation chamber or other places far away from the laser for processing.
4. The tool is not needed in machining, which belongs to non-contact machining and has no machining deformation.
5. It is easy to automatically control continuous machining without machining tools and special environment, with high machining efficiency and small machining deformation and thermal deformation.
Application of laser processing
With the development of modern industrial technology, there are more and more kinds of materials with high hardness and melting point, and they are used more and more. It is often required to make small and deep holes in these materials, such as gem bearings of clocks or meters, diamond drawing dies, chemical fiber spinnerets, and fuel nozzles in a rocket or diesel engines. This kind of processing task is very difficult to be realized by conventional machining methods, some of which are even impossible, while laser drilling can better complete the task.
In laser drilling, we need to know the drilling material and requirements in detail. Theoretically speaking, the laser can make small holes as shallow as a few microns and as deep as more than 20 millimeters in different positions of any material, but specific to a certain drilling machine, its drilling range is limited. Therefore, before drilling, it is better to fully understand the drilling range of the existing laser to determine whether it can be drilled.
The quality of laser drilling is mainly related to laser output power and irradiation time, focal length and divergence angle, focal position, energy distribution in facula, irradiation times and workpiece material, etc. these technological parameters should be reasonably selected in actual processing.
The principle of laser cutting is similar to laser drilling, but the workpiece and laser beam move relatively. In the actual processing, the laser numerical control cutting can be successfully realized by using the numerical control technology of the worktable.
Most of the laser cutting adopts a high-power CO2 laser. For fine cutting, YAG laser can also be used.
The laser can cut metal or nonmetal. In the process of laser cutting, because the laser does not produce mechanical impact and pressure on the material to be cut, and the laser cutting seam is small, which is convenient for automatic control, so it is often used to process glass, ceramics, various precision and small parts in engineering practice. In the laser cutting process, the main factors that affect the laser cutting parameters are laser power, blowing pressure, material thickness, and so on.