HARDNESS AND MORPHOLOGICAL CHARACTERIZATION OF TUNGSTEN CARBIDE THIN-FILMS

Ni doped Tungsten Carbide thin films (WC+Ni) were deposited onto stain less steel, WC-Co and glass substrates by non-reactive d.c. magnetron sputtering process using a sintered WC-6% Ni target. The WC+Ni hard co ating films had thicknesses between 0.6 and 1.5 mu m and were deposite d at temperatures between 300 degrees C and 550 degrees C. The structu re of the films was characterized using X-ray Diffraction (XRD), Secon dary Ion Mass Spectroscopy (SIMS) and Reflection Absorption Infrared S pectroscopy (RAIRS) techniques. A morphological analysis was carried o ut using Atomic Force Microscopy (AFM) and SEM, while the microhardnes s was measured by nanoindentation. Reflection Absorption Infrared Spec troscopy results confirm that the WC formation was dependant on substr ate temperature. AFM and SEM analysis indicated that the surface morph ology is formed by rounded grains. Hardness values deduced from microi ndentation curves by statistical average on each sample is 18 GPa for all the samples, the same value that has been found from the microinde ntation measurements an the bare WC substrate. (C) 1998 Elsevier Scien ce S.A. All rights reserved.