Hardness and wear characterization of titanium thin films obtained with a cathodic arc employing a magnetic concentrator

FRANKLIN BERMEO; ARIEL KLEIMAN; ADRIANA MÁRQUEZ

Mar del Plata

Workshop; 14th Latin American Workshop on Plasma Physics; 2011

Thin film growth with cathodic arc devices has been widely investigated due to this technique promotes the formation of dense, nano-structured films with good adhesion to the substrate and high deposition rate. In cathodic arc discharges a metallic plasma jet is ejected from the cathode surface. If a substrate is located facing the plasma jet its surface is coated with a metallic film. The main disadvantage of vacuum arc deposition is the emission of macro-particles (MPs) from the cathode. MPs in the coatings produce protuberances and depressions on the surface that not only increase the roughness, but also degrade mechanical properties. Employing a magnetic field parallel to the propagation direction of the plasma jet, the ions are concentrated on this direction and the plasma density increase, thus the deposition rate increases and the fraction of MPs decreases. In this work, Ti films were grown on stainless steel AISI 316 with a DC cathodic arc employing a magnetic concentrator. Substrates were placed facing the cathode at different distances respect to the entrance of the magnetic concentrator. Morphological and tribological features of the coatings were studied. The film surface was examined by SEM and the composition was analyzed by EDS. The uniformity of the films was studied with a colotester and with a profilometer. Hardness measurements were performed by a Nanovea nano-indenter and wear tests by a CSEM tribometer.