TiN coatings on polyurethane (PU) were produced by pulsed laser deposition using a system working with a Nd:YAG laser for ablation of titanium target. Nitrogen environment was applied in the reactive chamber in flow of 30sccm. Structure examinations X-ray diffraction (XRD), atomic force microscopy (AFM) and transmission electron microscopy (TEM) were performed to study surface morphology (AFM) and microstructure of the cross-section (TEM) as well as crystallographic texture and residual stresses (XRD). AFM results revealed diminishing of the roughness of the surface with rise of the coating thickness in the range from 0.25 via 0.5 and 1 up to 3m. Dominating contribution of kinetic processes in the formed morphology could be suggested together with the thickness rise due to appearance of the characteristic features on the surface leading to the polycrystalline fine grained microstructure. Extend of the lattice parameter was stated in XRD measurements with the increase of the coating thickness which could be explained by the change of deposition mechanism. Crystallographic texture measured in TiN layers presented close to random preferred crystallographic orientation as well as pole figures of the residual stress distribution suggested isotropic character. Thin foils prepared from the cross-section using microtom method showed a form of anchoring of the TiN deposited layer to the PU substrate with possible local remelting of substrate by the first deposited particles. Residual stress measured in TiN layer was in the range of about -2GPa and its value diminished together with the rise of the coating thickness. Biological tight examinations of coating are carried out in the range of cell proliferation, death and adhesion.
Financial support of the work by project PBZ-KBN-082/T08/2002/11