Abstract: Hard coatings for mechanically and corrosively stressed elements are applicable to arbitrarily chosen substrate materials. The mentioned elements can be tools, cutting inserts or bearings. Further, applications are possible in electronics and optics and also for decorative purposes. Hard coatings on the basis of carbon and boron nitride, produced by known techniques, are obtained which can be used in a wide field of application, exhibiting, besides a high hardness, maximum adhesion and good protection against wear and corrosion at high temperatures. The C and B/N coatings consist of amorphous network structures with short range orders similar to that of the hexagonal crystalline phases of carbon and boron nitride, have hydrogen concentrations between 5 atom-% and 50 atom-% and additional components consisting of metals and/or boron and or silicon and/or noble gases in the concentration range between 1 atom-% and 85 atom-%.