Deposition and characterization of hard coatings in the material by ujl89480

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Deposition and characterization of hard coatings in the material system V-Al-N
                 by reactive magnetron sputter deposition

                             1              2                3              4
             Szilárd Kolozsvári , Peter Pesch , Carlos Ziebert , Sven Ulrich
    1,2
          TZO-Technologiezentrum für Oberflächenzentrum Rheinbreitbach GmbH,
                                      3,4
           Rheinbreitbach, Germany Forschungszentrum Karlsruhe Institut für
                Materialforschung I , Eggenstein-Leopoldshafen, Germany


                                 kolozsvari@tzo-gmbh.de


Binary and ternary hard coatings in the system V-Al-N (VN, AlN and VAlN) were
deposited by reactive dc and r.f.-magnetron sputtering in an Ar/N gas mixture from a
V target and/or Al target. For each experiment, Si (100) substrates and polished
1.2379 steel substrates were placed on the rotating substrate table. VN coatings
were deposited at a constant Ar gas flow of 250mln, while the bias voltage applied to
the substrate table was systematically varied between -80 and -200V. The influence
of this variation on the mechanical properties was examined. For the deposition of
AlN and VAlN coatings the bias voltage, the Ar:N ratio and the total gas pressure
were varied. The chemical composition of the obtained coatings was determined by
electron microprobe analysis and the crystal structure of the films was characterized
by X-ray diffraction. The mechanical properties hardness and reduced elastic
modulus have been investigated by microindentation and the critical load of failure by
scratch test. The surface roughness of the as-deposited samples was examined as a
function of the initial substrate surface roughness. It was possible to achieve a large
variation of the hardness in the range between 700HV 0.0005 and 3100HV0.0005 and in the
reduced elastic modulus in the range between10 and 30 GPa. Finally, the specific
conditions for the formation of large-area VN, AIN and VAlN nanofilms in
industrial-size coating facilities are described in terms of process engineering.


Keywords:
valn, vn, aln
magnetron sputtering
hard coatings
bias variation
pressure variation

								
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