Plasma cutting can be sub-divided into flame and fusion cutting, and is suitable for non- and low-alloy steel, but especially for high-alloy steels and non-ferrous metals. An arc provides the energy to melt the material or heat it to ignition temperature. The liquid material or slag can then be combusted or squeezed out of the joint by the cutting gas. At low sheet thicknesses, plasma cutting is inferior to laser beam cutting with respect to cut quality, but with higher sheet thicknesses it is more economical. Especially high cut quality can be achieved with fine-beam plasma cutting.