non-transferred arc
and can be realised with power higher than some
MW. The produced plasma is mainly utilised to
destroy toxic-harmful substances or, as in the case
of the plasma spray, to produce coatings of thick
films. The second type of plasma, named cold or
non-equilibrium plasma, is characterised by the
electron temperature higher than the ion temperature; it is produced under vacuum conditions using
low power rf or microwave or dc sources. The
interactions of the plasma particles on the
materials produce the modification of the surfaces
in order to add different functional properties with
respect to the bulk material.