Deposition And Ivestgation On Properties Of (Ti, Al)N-Based Superhard Film By Magnetron Sputtering

In this article,the development of vacuum deposition technique, TiAlN films and TiAlN–based superhard films were described at first. The structure, properties and applications of TiAlN film and TiAlN–based superhard films were summarized. The physical vapor deposition technique and fundamental principle of magnetron sputtering were introduced simply in it. Based on this, advanced quaternary TiAICrN films were produced on Si(111) and stainless steel substrates respectively by reactive magnetrons co-puttering technique. Diferent Cr content, microstructures, properties and surface morphologies of these films were obtained under various Cr target puttering power. X-Ray Diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), and nano-indentater measurements were used to observe and analyse the microstructures, micro-morphologies and mechanical properties of the films. Chemical compositions were determined by energy-dispersive X-ray (EDX) analysis and potentiodynamic polarization measurements of study of the corrosion behavior of films were performed using galvanostat and potentiostat system. By discussion, the following conclusions can be achieved.For all TiAIN films, crystals and amorphous were presenced. The grains was smaller than TiAlN's by introducing Cr in it .The thichness of TiAICrN films increased first, and then decreased with Cr target sputtering power increasing. It was probably caused by the high energy particles at higher Cr target sputtering power produced unsputtering on the substrates.Changes of micro-morphologies and surface roughness of the films were obvious: as theCr content increased, the grain size and surface roughness decreased first, and then increased slightly. Compare to TiAlN, TiAICrN films were smoothness, condensation; its grains were smaller, surface roughness was lower and no pore and blow-up.When Cr content increased, the nano-hardness increased first, and then decreased, but the modulus were affected little only. The critical load of TiAICrN films increased with Cr target sputtering power increasing. The first critical load of all TiAICrN films was higher than TiAlN's, and the second critical load was twice nearly to it. So, TiAICrN films showed good adherent to substrates. Potentiodynamic polarization measurements indicated: the corrosion resistance of TiAICrN films were better than SS and TiAlN films and increased with Cr content increasing. when Cr content was 25.5at%, the optimum quality of the TiAICrN film was achieved with the smallest grain size and surface roughness value, the top micro-hardness, the biggest the first critical load, and the best corrosion resistance.