H.A. Castillo

Synthesis of Ti/TiN/TiCN coatings grown in graded form by sputtering dc

Graded coatings have the advantage of having gradual properties such as thermal expansion coefficient and lattice parameter, avoiding adherence problems due to good match between their component materials. In this work, some properties of coatings grown in graded form are presented. The materials were produced using the sputtering dc technique because of its facility to control the deposition parameters and generate homogeneous growth. The target is a disc of titanium and the samples are made of stainless steel 304. The working gases are argon, nitrogen and methane, which are mixed according to the material to be produced. Titatnium (Ti) layer is grown with argon, the titanium nitride (TiN) film is produced with a mixture of argon and nitrogen, and the titanium nitride carbon (TiCN) material is obtained mixing argon (Ar), nitrogen (N2) and methane (CH4). These materials are characterized with scanning probe microscopy (SPM) in atomic force microscopy (AFM) mode in order to determine grain size and with x-ray photoelectron spectroscopy (XPS) studying the chemical composition and performing depth profiles.

Effects of the Substrate Temperature in AuN Thin Films by Means of X‐Ray Diffraction

Gold is used in electronic industry like electric conductor for products such as computers, mobiles phones, etc; with the drawback that it is one of the most expensive metals in the market. Gold Nitride is a new material, having excellent physics properties like high hardness, high melting point, high electric conductivity, chemical inertia and good thermodynamic stabily among others. At the moment its study is more about electronics, optics, mechanical properties and growth of the films. AuN thin films were produced by the PAPVD (Plasma assisted Physics Vapor Deposition) method, using the pulsed arc technique in a mono-vaporizer system. These films were created with an Au target of 99% purity and deposited on stainless steel 304. It was observed that heating the substrate produces small stoichiometric changes in the film, which makes small changes in the diffraction patterns to appear, like widening in the Au orientation, since the composicional gradient is varying according to the substrate temperature. Au 4f and N1s narrow spectra were analyzed using XPS (X-Ray Photoelectron Spectroscopy), in order to observe stoichiometry in the films.

Chemical and morphological properties of (Ti-Zr)N thin films grown in an arc pulsed system

Due to its extensive field of application in different areas, including mechanics, electronics, tribology and optics the last decade has seen a large interest the study of titanium-zirconium-nitride (Ti-Zr)N thin films grown by different techniques. We had produced (Ti-Zr)N thin films and in this work chemical, morphological and electronics analysis are presented. Thin films were produced by the PAPVD (plasma assisted physics vapor deposition) technique, by pulsed arc in a mono-vaporizer system using a titanium-zirconium target with 99.99% purity. Argon-nitrogen mixture for the discharge was used. For the analyses X-ray photoelectron spectroscopy (XPS) and scanning probe microscopy (SPM) techniques were used, XPS results shown the chemical composition of the films. Films were morphologically and tribologically characterized using SPM, obtaining grain size and friction coefficient.

Study of W/WC Coatings Varying the Substrate Temperature

Tungsten carbide is considered a very important material used for industrial applications due to their high hardness. In this work the production of W/WC coatings used a repetitive pulsed arc system is employed. During the grown process, the substrate temperature is varied in order to identify the influence of this parameter in the structure, composition and morphology of the coatings. The layer of W is grown to improve the adherence of the WC material on the stainless steel 304. To grown the coatings, it was used a W target in the cathode. The gas of work is methane and as it is knew, to use a gas as precursor for WC production causes the apparition of different phases as WC and W2C. The power supply allows varying the active and passive time of pulses, which in this case have a value of 1 s. the coatings produced are characterized by X‐ray diffraction (XRD), X‐photoelectron spectroscopy (XPS) and scanning probe microscopy (SPM). All of these techniques allow determining properties such as chemical compo...