Assist gases and air of Ruijie laser
Fiber Laser cutting needs Nitrogen and Oxygen to assist the cutting process. O2 is used while cutting MS, and across the globe, people use N2 on SS to get a very fine finish. O2 on SS brings a carbonising effect on the cut surface and demands post processing.
And the major point in using O2 in the cutting process is that O2 oxidises the metal. It actually induces the cutting process. Using O2 enable the Laser to penetrate deep into the metal. So the cutting thickness could be increased using O2. In case of N2, it cools down the metal during the cutting process. So, for a fine finish, it’s advisable to use N2 in the cutting process so that the HAZ is drastically reduced. These are the two principles to be considered in using assist gasses.
The second thing is about the purity of the assist gasses. There are certain purity criteria for assist gasses for it to be used in Laser cutting process. The common purity level of assist gasses is 99.98%. It’s generally advisable to use the highest level of purity available. Any deviation in the cutting quality has a direct impact on the cutting finish. Gas pressure too determines the cutting process.
Third is the Air pressure. During the cutting process, a cavity is formed between the actual component and the parent metal sheet. This cavity is actually the molten state of the metal. Laser heats the metal until it melts. The molten metal when separated/ removed is when the cutting happens. And for the separating process, air is a must. Hence air pressure has a very critical role to play in the quality of finish.
Post time: Feb-13-2019