What is the difference between oxygen and nitrogen as auxiliary gas of fiber laser cutting machine

Oxygen, compressed air, nitrogen and inert gases are more common auxiliary gases.

The fiber laser cutting machine is a thermal processing process in which the laser beam is aligned with the processing tool, and specific parameters need to be used during the processing. The decisive factors of the cutting quality and processing time of the workpiece are the power and the type of auxiliary gas. Oxygen and nitrogen are the most commonly used auxiliary gases. In actual processing, the choice of a certain gas is determined by the type of material, the thickness and the required edge quality.

In general, oxygen is the most commonly used auxiliary gas when working with fibre laser cutting machine. Thin steel does not need a lot of substitution due to its combustion process. The combustion process involves the chemical reaction of oxygen and iron, which releases a lot of quantum and light energy. The cutting speed using oxygen as the auxiliary gas for thin steel will be the same for a laser cutting machine fiber of 1500 watts to 6000 watts.

Nitrogen is usually used as an auxiliary gas when cutting stainless steel or aluminum. Nitrogen prevents gas when the steel laser cutting machine cuts the material, preventing the combustion process from aiming at the laser to quickly vaporize the material to achieve better cutting quality. The role of oxygen is different.

Power is a decisive factor affecting the cutting speed.Generally speaking, the faster the power increases.

In various application industries of laser, laser power has been steadily increasing. Through the continuous development of technology, customers have more choices.

In order to make the right decision between oxygen and nitrogen, the following criteria must be considered:

(1) Processing speed

(2) Secondary processing, including the required edge quality

(3) Operating cost

Let us examine these three factors in detail:

Processing speed

As mentioned earlier, the oxygen cutting speed is limited by the power that can be applied by the laser cutting for steel machines, while the nitrogen cutting speed is directly related to the power. Under certain circumstances, when cutting thin steel, the processing speed with nitrogen and higher laser power may be three to four times faster than when using oxygen.

Secondary processing

When nitrogen is used as the auxiliary gas, the cutting surface is very smooth and smooth, which is very suitable for powder coatings, and can also be used as a welding surface, and this cutting method usually does not require any secondary processing. However, the oxide surface produced by oxygen cutting will affect the powder coating and welding, and sometimes the surface needs to be treated. The brake is suitable for powder coating.

Operating cost

The consumption rate of nitrogen is 10 to 15 times that of oxygen, and the cost of oxygen is reduced. Generally speaking, the thickness is reduced. The consumption of nitrogen as auxiliary gas will also increase.

Taking all factors together, the following goals can be made:

When using a laser cutting machine for metal sheet to process thin steel, if you are willing to pay a higher cost to produce higher quality parts, you should choose nitrogen as the auxiliary gas. With the increase in material thickness, it becomes difficult to cut with nitrogen. If the parts to be produced require secondary processing, the user must weigh the cost of additional processes and processing, how to use nitrogen and oxygen, and more specific arithmetic.