Duplex treatment on AISI D2 tool steel: plasma nitriding and reactive deposition of TiN and TiAlN films via magnetron sputtering

Abstract

In this work, titanium nitride (TiN) and titanium aluminum nitride (TiAIN) films have been obtained via triode magnetron sputtering. The films were deposited using a direct current source on plasma nitrided AISI D2 tool steel (duplex treatment), non-nitrided steel, and silicon. The nitrided layer was characterized by scanning electron microscopy (SEM), Vickers microhardness, and X-ray diffraction (XRD). The films were characterized by SEM and XRD. The mechanical properties of the coatings were determined using the instrumented indentation technique (IIT) and the adhesion of the film to the substrate was qualitatively evaluated using the Rockwell C test. Both films presented no significant variation in hardness (H) and elastic modulus (E). However, compared to the films obtained in non-nitrided steel, the duplex treatment improvided the film-substrate adhesion. The improvement in adhesion can be attributed to the preliminary plasma nitriding treatment and the compressive loads acting on the nitrided surface.