How To Cut Galvanized Steel With Laser Cutting Machine?

Galvanized steel is widely used in the manufacture of automobile bodies because of its excellent corrosion resistance, and it is also a common metal material used in the manufacture of home appliances, filing cabinets and daily necessities, etc. In order to ensure the precision and quality of product molding, laser cutting is the most common process used in the galvanized sheet materializing process. It is a means of processing without contacting the material, so there will be no damage to the surface of the sheet, as well as the cut-off surface will not leave a burr, is a processing method that can significantly reduce the number of back-end processes.

Since galvanized sheet is coated steel, it has been recognized as a difficult material for laser cutting. Today, the most mainstream laser cutting equipment to fiber laser cutting machine, which has great advantages in cutting costs and maintenance. So, what are the better solutions for fiber laser cutting machine in cutting galvanized sheet?
As we all know, the role of galvanized steel plate is to protect the carbon steel inside by galvanizing the surface, and it is a kind of plate that is not easy to rust even after long-term use. Although this kind of plate will be slightly more expensive than ordinary carbon steel plate, but because there is no need to spraying and other post-processes in order to prevent rust, so from the cost point of view, it is still cost-effective.
In the process of processing galvanized sheet, you need to add auxiliary gases, auxiliary gas purity affects the quality of the cut sheet section, cutting oxygen purity should be 99.6% or more, when cutting oxygen purity is higher, cutting galvanized sheet section of the quality is also higher, of course, the cost of cutting is also increased. Cutting nitrogen purity should be 99.5% or more, improve nitrogen purity can ensure that in the process of cutting galvanized sheet cutting seam does not change color.
Then from the auxiliary gas point of view, there are generally three cutting processes for galvanized steel, namely air cutting, oxygen cutting and nitrogen cutting. Let's analyze the advantages and disadvantages of each of these three cutting processes:
First, air cutting: the advantage is that the processing cost is extremely low, only need to consider the laser itself and the electricity cost of the air compressor can be, without the need to produce expensive auxiliary gas costs, but the cutting efficiency in the thin plate can match the nitrogen cutting, is an economical and efficient cutting method. However, the disadvantages on the cutting surface are equally obvious. First of all, the air cut section will produce bottom burrs, laser processing of the product must also be deburred and other secondary processing, is not conducive to the entire product production cycle. Secondly, air-cut sections are prone to blackening, which affects the quality of the product. Therefore, the advantages of laser processing without subsequent processing can not be reflected, so in the processing of galvanized steel, many companies are not willing to choose air cutting.
Second, oxygen cutting: this is the most traditional and standard cutting method. The advantage is that the gas cost is low, and in the sheet metal processing of carbon steel-based, without frequent switching of auxiliary gases, easy to manage the factory. However, the disadvantage is that after oxygen cutting, a layer of oxidized skin will remain on the surface of the cut-off surface. If this product with oxidized skin is directly welded, the oxidized skin will naturally peel off after a long time. This is one of the reasons why galvanized sheet metal welding is easy to weld.
Third, nitrogen cutting: the use of nitrogen for high-speed processing, due to the use of nitrogen is different from the role of flammable oxygen, but to play a protective role, so the cutting section will not produce oxide skin. Many companies are also looking at this advantage, so the cutting of galvanized steel will often use nitrogen for processing. But the disadvantage of nitrogen cutting is also here: because the cutting section is completely unprotected, so the product is easy to rust. In order to prevent the product from rusting, it has to be sprayed again, as a result, spend more money to buy back the galvanized sheet, but also did not play out the characteristics of its galvanized layer to, I have to say quite a pity.