The present thesis deals with precise investigations of hard coatings and the interrelationship between the mechanical properties and the coating structure. The coating syntheses in the system Ti-N occurred via reactive magnetron sputtering, coatings in the systems Ti-B and Ti-B-N were prepared by non reactive magnetron sputtering. In order to attain a variation of the coating properties, the deposition parameters were varied so that two essential conditions changed. These were the connection between ion flux and Ti flux (Jion/JTi) [(J tief ion / J tief Ti)] and the energy of the ionic bombardment (Ei) [(E tief i)] during coating growth. The conclusively changed nanostructure of the coating has a strong influence on the mechanical properties. In order to compare the coatings with each other, they were characterized with respect to their crystallographic constitution (X-ray diffraction), residual stresses (cantilever beam test), the ductility (Four-point bending test and indentation experiments), chemical composition and hardness (microhardness testing). The X-ray diffraction-investigations showed a direct dependence of the grain size and orientation on the used deposition parameters. Moreover a direct relation of the coating residual stresses on the ion bombardment. A variation of the ion bombardment leads to different grain sizes and defect densities and thus to different residual stresses (tensile or compressive residual stresses) in the coatings. For Ti-N the highest residual stresses where measured are about -13 GPa. The highest hardness is about 52 GPa. In the coating system Ti-B the maximum coating residual stress achieved is about -2.3 GPa and the highest hardness is about 60 GPa. Coatings within the Ti-B-N system exhibit residual stresses of approximately -950 MPa.<br />Their maximum hardness is about 37 GPa. By virtue of the precise characterization of the chemical composition, the microstructure, and the residual stresses of the coatings their individual influences on the hardness and ductility of coatings in the systems Ti-N, Ti-B and Ti-B-N can be shown.