Metallization means the application of a layer of pre-melted metal to the surface of the metallized product. In other words, it is the hot spraying of the product. This technology is also referred to as lapping. Metallization is used as a surface protection of a product or its components where increased chemical corrosion resistance of the substrate material is required.

In metallization, the metallizing material - zinc or aluminum - is melted in a metallizing gun and accelerated against the surface by pressurized air. In metallization, however, not all of the material sticks to the surface to be treated, but only a part of it. During metallization, the remaining material is spread into the metallization box and needs to be very intensively sucked out and the air filtered. The air and the metal particles form an explosive mixture and the air extraction and filtration system must therefore be designed for the extraction of explosive dusts. The metal particles that enter the extraction system are already in the solid state again.