Different Techniques in Laser Cutting

Laser cutting is not all about dividing a material in two parts. There are many different techniques in the laser cutting process. These techniques greatly expand what a laser machine is capable of.

Here are all the different ways in which you can use a laser cutting machine:

Vaporization Cutting

Vaporization Cutting is also known as Sublimating. Usually, on heating, solid materials reach the melting point and then the boiling point. However, in vaporization cutting, the laser beam raises the temperature of the material at a very fast speed. The material directly reaches the boiling point and begins to vaporize. There is no melting caused and no time for heat conduction. This results in a very precise and narrow cut.
This cutting process only applies to the thin sheet metal of ferrous materials. It does not apply to materials that don’t have a boiling point, like wood. Additionally, it requires a very high-powered laser beam to work.

Fusion Cutting

Fusion cutting is also known as Melt and blow cutting. Melt and blow cutting is the basic form of laser cutting. The laser beam melts the workpiece material. A blower then removes the melted material, thereby separating the workpiece. The melt and blow cutting method can cut thicker materials with ease.

It is important to use an inert gas in the fusion cutting technique. Non-inert gas will react with the workpiece due to the material’s high temperature. Inert gas flow ensures no inadvertent chemical reaction occurs.

Laser Flame Cutting

Laser flame cutting is also known as reactive cutting and oxidation melting cutting. Oxygen gas aids in the cutting process in addition to the laser beam. Oxygen gas is blown to the workpiece along with the laser beam. The laser ignites the oxygen, which turns into a high-temperature blow torch. The material is weakened with the oxygen flame and the laser heat, resulting in faster cutting.

Laser flame cutting is considerably faster than other laser cutting techniques. However, the cut quality and accuracy deteriorate. Additionally, the kerf width increases in this method. It is possible to replace oxygen with any other reactive gas.

Fracture Controlled Cutting

Fracture-controlled cutting is also known as thermal stress cracking. It is applied when cutting brittle materials. When uncontrolled force or temperature is applied, brittle materials tend to break into pieces. Fracture-controlled cutting focuses a very narrow laser beam on a small workpiece surface. It creates a thermal gradient that cracks the workpiece in that location. The laser then moves in a very fast and controlled manner to spread the crack along the cut.

Fracture-controlled cutting is commonly applied when cutting glass and ceramics. The laser is not passing completely through the material thickness. Only a portion of the thickness is cut and the rest separates due to cracking.

Stealth Dicing

Stealth dicing is an advanced laser-cutting technology used for slicing semiconductor wafers. It works in two phases- the laser irradiation phase and the expansion phase. The laser does not melt the workpiece because that would create unwanted molten material. Instead, the irradiation phase uses a laser wavelength that passes through the workpiece completely.

However, this wavelength creates internal deformations and cracks in the workpiece. The expansion phase then creates expansive stress on the workpiece. This stress separates the workpiece into many pieces at the areas of internal defects. The end result is a clean-cut wafer with no dross.

Vector Scoring

Vector scoring is a laser-cutting technique for engraving the workpiece. The laser does not pierce through the entire thickness of the material. Instead, the laser will follow the travel direction specified by the vector.

The thickness of the engraving can be easily adjusted by defocusing the laser beam. The depth of the engraving can also be adjusted. Vector engraving can create simple, straight lines to complex designs.