High-quality edges for precision cutting.
In this process, the idea is to use the laser to vaporize the material with as little melting as possible. In the kerf, the material vapor creates high pressure that expels the molten material from the top and bottom of the kerf.
The process gas – nitrogen, argon, or helium – serves solely to shield the cut surfaces from the environment. It ensures that the edges remain oxide free. For this reason, a gas pressure of 1 to 3 bar is sufficient.
More energy is needed to vaporize metal than to melt it. For this reason, sublimation cutting requires high laser power and is slower than other cutting processes. However, it produces high-quality cuts.
This process is rarely used in sheet metal fabrication. Its use, however, becomes attractive in applications involving particularly delicate cutting work. Such applications include the production of stents.
In metal processing, sublimation cutting is the exception;
with nonmetals, it is very common. Many non-metal materials are regularly processed with sublimation cutting. Typical materials include:
• Plastic sheeting and textiles, which vaporize even when only a small amount of energy is applied
• Materials that do not melt, such as wood,
cardboard, or foam