  Experimental data are given on the structure and properties of
nanocrystalline hardening coatings of titanium nitride doped with copper,
produced by plasma-assisted vacuum arc deposition by evaporating powder
cathodes. A model of nanostructurization of this type of coatings is proposed.
According to the model, the nanocrystallization in these materials is due to
the dopant atoms, which form an amorphous sheath around a crystallite, thus
defining its size.
