Metal Cutting
Laser cutting of metal materials
There are two main cutting techniques in laser cutting of metals.

1. Fusion cut
2. Flame cut

The Laser Fusion Cutting process is used where parts are required to meet high optical requirements without the need for post-processing. In fusion cutting, the laser beam melts the metal along the entire cutting line, while an inert gas stream at high pressure blows the molten material out of the cutting cavity. The laser fusion cutting process uses nitrogen or argon inert gases that inhibit reactions. The noble gases do not react with the molten metal contained in the cavity, but blow it away. These inert gases used cool the material and prevent oxidation at the cutting edge. The fusion cutting process, which provides the advantage of completely oxide-free cut edges, is used in cutting high alloy steel, stainless steel and aluminum because it creates clean, bright, dross-free edges.

The Laser Flame Cutting process allows high cutting speeds, processing of thick plates and mild steel. In flame cutting, the laser beam heats the metal surface above a certain temperature along the desired cutting line. Oxygen is used as the cutting gas and is blown into the cutting cavity. Here it causes an exothermic reaction and melts the metal. This oxidation releases more energy and assists the cutting by supporting the laser beam. The flame cutting process is faster than the fusion cutting process, but the cutting edge it leaves behind is oxide coated, so the cutting edge quality of the fusion cutting method is better.

Laser cutting of mild (carbon) steels
In principle, laser cutting of metals is accomplished by locally heating the material to the melting point of the material at the focal point of the focused laser beam. The molten material is blown out by a gas directed coaxially to the laser beam to form a cut cavity.

Especially in low alloy steels, oxygen is used as cutting gas. Mild steels are the most common cut materials in the industry. For example, laser cutting of gears, cladding, chain links from mild steel...