Investigation of the surface properties of the thin films deposited by magnetron sputtering technique on free-form shaped Tİ13NB13ZR alloy surface

The biomedical Ti13Nb13Zr alloy, developed as an alternative to Ti6Al4V alloy, has a low modulus of elasticity, high mechanical properties, high corrosion resistance, high biocompatibility, and low modulus of elasticity, as well as containing no cytotoxic elements, making it a favorite candidate for orthopedic joint implant applications. However, the low tribological properties of the alloy limit its use in this field. Tribological properties can be improved with thin ceramic films made on the surfaces of the alloys by various methods without compromising the bulk properties of the alloys. In this thesis, in order to improve the tribological and mechanical properties of ASTM F-1713 Ti13Nb13Zr alloy, its surface is coated with multilayer thin films consisting of different components by unbalanced magnetic sputtering technique in a closed area. In all coatings, a thin Titanium adhesion layer was deposited on the surface of the alloy, and a TaN thin film was deposited on the top surface. In the repeating interlayers, using three different coating models as TiN/TiCN, TiC/TiCN, and TiN/TiC/TiCN, the number of interlayers was changed, and thin films in six different coating architectures were deposited on Ti13Nb13Zr samples with a flat surface of 20 mm in diameter and 2 mm in thickness. As a result of the characterization experiments, 20 layered Ti/ 6x(TiN/TiC/TiCN) /TaN coating showed the best results in terms of adhesion to substrate, mechanical and tribological properties. Freeform-shaped Ti13Nb13Zr alloys with a radius of curvature R14, R18, and R22 were coated with this coating architecture by using the same coating parameters via the same method. The tribological properties of the coatings were investigated in a specially developed abrasion test setup and UHMWPE which is used in orthopedic joint implant applications, was used as the counter material. As a result of the wear tests performed in a total of 5 million cycles, it was determined that the thin film surface continuity decreased due to the increasing radius of curvature. In addition, it was observed that the coatings were subjected to adhesive delaminations due to stress concentrations and poor adhesion near the sample edge.