Cutting is probably one of the most well-known laser processing applications. As early as the 1970s, the laser was first use for cutting. At that time, the laser used was 200W-500W CO2 laser. In the following decades, laser cutting machines were widely use in industrial production. Nowadays, with the development of laser cutting technology, various processes have emerged endlessly. Below we introduce to you three commonly used laser cutting processes.

Flame cutting:

Flame cutting is a standard process use when cutting mild steel. And various kinds of oxygen are use as cutting gas. Oxygen is pressurize up to 6 bar and blown into the incision. There, the heated metal reacts with oxygen: it begins to burn and oxidize. The chemical reaction releases a large amount of energy (up to five times the laser energy) to assist the laser beam in cutting.

Flame cutting makes high-speed cutting possible, and it can cut thick plates, such as low carbon steel with a thickness of more than 30mm. However, this process also has disadvantages. The cutting edge is covere by an oxide layer. The oxide layer must remove before painting or matting the parts, otherwise the paint and coating will not be able to adhere to the surface, there is no protective coating, and the parts are not resistant to corrosion.

Melt cut:

Melt cut is another standard process use when cutting metal. But it can also use to cut other meltables, such as ceramics. Here, nitrogen or argon use as the cutting gas, and the pressure is blow through the incision from a gas of 2-20 bar. Argon and nitrogen are inert gases, which means that they do not react with the molten metal in the cut and just blow them away to the bottom. At the same time, the inert gas can protect the cutting edges from being oxidize by air.

Almost all metals can use nitrogen, especially titanium. Titanium reacts violently with oxygen and nitrogen, so argon is used when cutting titanium. The great advantage of melt cutting is that there is no oxide layer on the cutting edge and no further processing is required. However, the laser beam needs to provide all the energy for cutting. For this reason, cutting speeds like flame cutting can only be achieved when cutting very thin sheets. Melting perforations is also difficult, and some cutting systems allow you to pierce the material with oxygen and then cut with nitrogen.

Compressed air cutting:

For those who do not want to purchase cutting gas, compressed air can also be used to cut thin plates. Pressurizing the air to 5-6 bar is enough to blow away the molten metal in the cut. Since nearly 80% of the air is nitrogen, compressed gas cutting basically belongs to melting cutting. On the surface, compressed air cutting seems to provide a relatively economical alternative to nitrogen, after all, air is free. However, you must compress, dry, and remove any oil that may appear.

With that in mind, a more realistic image emerged as to whether it has a cost advantage over nitrogen. The air pressure and laser power achieved by the air compression system determine the thickness of the material that can be cut. For example, a 5kw laser and 6bar compressed air can cut 2mm thick boards without leaving burrs. In general, the cutting edges are rougher than those cut with nitrogen melting, and air-assisted cutting works best on aluminum.

Sheet metal processing was the past, and it is still the main object of laser cutting. When the object is a flat plate, deep parts or profiles, laser cutting has obvious advantages over traditional methods. Not just sheet metal, lasers can also cut a variety of other materials, such as plastics, glass, ceramics, semiconductors, and textiles, wood and paper. The types of applications are also diverse. Not only for thick, solid and large parts, fine machining and micromachining are actually very popular. Experts believe that applications in this area will see substantial growth in the coming years.