Changes in the Mechanical Properties of Ti Samples with TIN and　TiN/TiO2 Coatings Deposited by Different PVD Methods

摘要

The metallic implants represent a major class of the hard tissue replacement materials. In order to enhance the surface properties of the titanium alloys multicomponent coatings containing ceramic phases are employed to improve the tribological performance, corrosion resistance and biocompatibility. The mechanical properties (elastic modulus, necking region, loss of adhesion) of arc PVD TiN and TiN/TiO2 coatings deposited on unalloyed Ti (99 wt. %) foil were examined by nanoindentation, uniaxial tensile test while applying a new approach -using thermal imaging camera during the test. The hardness of the TiN coating reached values of 9649 MPa and 67 GPa, while that of the TiN/Ti02 was lowered down to 8774 MPa and 58.5 GPa which low values are closer to that of the cortical bone. The mechanical behavior of TiN/Ti02 coated material characterized it as a more plastic system indicating a good deformability while the TiN displayed more fragile behavior. There were no signs of loss of adhesion or loss of coating integrity up to maximum load for all tested TiN and TiN/TiO2 coated samples. The thermal analysis proves that the coated samples show lower thermal conductivity, which is very important for the performance of an endosseous dental implant for example.