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Title: Tailored synthesis of TiC/a-C nanocomposite tribological coatings

Abstract

Composite coatings made of nanocrystalline TiC (nc-TiC) particles and amorphous carbon (a-C) have been prepared in a double magnetron sputtering system using graphite and titanium targets under Ar bombardment. Chemical composition and microstructure of coatings were studied by transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), and x-ray diffraction (XRD) for a set of samples prepared varying the ratio and intensity of power applied to each magnetron. Changes in coatings microstructure, from a quasipolycrystalline TiC to a nanocomposite formed by nanocrystals of TiC embedded in an amorphous matrix of carbon (nc-TiC/a-C), are observed depending on the synthesis conditions. Tribological and mechanical properties of coatings were tested using a pin-on-disk tribometer and an ultramicrohardness indenter, respectively. Coatings with moderate hardness (7-27 GPa), low friction (0.1-0.2), and low wear rates (k{approx}10{sup -7} mm{sup 3}/N m) were obtained. A percentage between 15% and 30% of TiC is found as an optimum value to get a good compromise between good mechanical and tribological properties. Finally, a mapping of the mechanical and tribological properties of the nc-TiC/a-C system is presented for the synthesis conditions employed.

Authors:
; ; ; ; ; ; ;  [1];  [2]
  1. Instituto de Ciencia de Materiales de Sevilla, Centro Mixto CSIC-Universidad de Sevilla, Avda. Americo Vespucio 49, 41092-Sevilla (Spain)
  2. (Spain)
Publication Date:
OSTI Identifier:
20723218
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 23; Journal Issue: 6; Other Information: DOI: 10.1116/1.2101810; (c) 2005 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AMORPHOUS STATE; CHEMICAL COMPOSITION; COATINGS; COMPOSITE MATERIALS; CRYSTAL STRUCTURE; DEPOSITION; ELECTRON SPECTROSCOPY; ELECTRONS; FRICTION; GRAPHITE; MICROHARDNESS; MICROSTRUCTURE; NANOSTRUCTURES; PRESSURE RANGE GIGA PA; SPUTTERING; SYNTHESIS; TITANIUM; TITANIUM CARBIDES; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Martinez-Martinez, D., Lopez-Cartes, C., Justo, A., Fernandez, A., Sanchez-Lopez, J.C., Garcia-Luis, A., Brizuela, M., Onate, J.I., and Fundacion INASMET, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian. Tailored synthesis of TiC/a-C nanocomposite tribological coatings. United States: N. p., 2005. Web. doi:10.1116/1.2101810.
Martinez-Martinez, D., Lopez-Cartes, C., Justo, A., Fernandez, A., Sanchez-Lopez, J.C., Garcia-Luis, A., Brizuela, M., Onate, J.I., & Fundacion INASMET, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian. Tailored synthesis of TiC/a-C nanocomposite tribological coatings. United States. doi:10.1116/1.2101810.
Martinez-Martinez, D., Lopez-Cartes, C., Justo, A., Fernandez, A., Sanchez-Lopez, J.C., Garcia-Luis, A., Brizuela, M., Onate, J.I., and Fundacion INASMET, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian. Tue . "Tailored synthesis of TiC/a-C nanocomposite tribological coatings". United States. doi:10.1116/1.2101810.
@article{osti_20723218,
title = {Tailored synthesis of TiC/a-C nanocomposite tribological coatings},
author = {Martinez-Martinez, D. and Lopez-Cartes, C. and Justo, A. and Fernandez, A. and Sanchez-Lopez, J.C. and Garcia-Luis, A. and Brizuela, M. and Onate, J.I. and Fundacion INASMET, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian},
abstractNote = {Composite coatings made of nanocrystalline TiC (nc-TiC) particles and amorphous carbon (a-C) have been prepared in a double magnetron sputtering system using graphite and titanium targets under Ar bombardment. Chemical composition and microstructure of coatings were studied by transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), and x-ray diffraction (XRD) for a set of samples prepared varying the ratio and intensity of power applied to each magnetron. Changes in coatings microstructure, from a quasipolycrystalline TiC to a nanocomposite formed by nanocrystals of TiC embedded in an amorphous matrix of carbon (nc-TiC/a-C), are observed depending on the synthesis conditions. Tribological and mechanical properties of coatings were tested using a pin-on-disk tribometer and an ultramicrohardness indenter, respectively. Coatings with moderate hardness (7-27 GPa), low friction (0.1-0.2), and low wear rates (k{approx}10{sup -7} mm{sup 3}/N m) were obtained. A percentage between 15% and 30% of TiC is found as an optimum value to get a good compromise between good mechanical and tribological properties. Finally, a mapping of the mechanical and tribological properties of the nc-TiC/a-C system is presented for the synthesis conditions employed.},
doi = {10.1116/1.2101810},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 6,
volume = 23,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
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  • Abstract not provided.
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