ICMCTF 2012! - CD-Lab Application Oriented Coating Development

Hard Coatings and Vapor Deposition Technology
Room: Royal Palm 4-6 - Session B1-2
Monday Afternoon, April 23, 2012
PVD Coatings and Technologies
Moderator: P. Eklund, Linköping University, Sweden, J.H.
Huang, National Tsing Hua University, Taiwan, J. Vetter,
Sulzer Metaplas GmbH, Germany
1:30pm B1-2-1 Effect of vacuum arc plasma state on the property of
nitride coatings deposited by conventional and new arc cathode., S.
Tanifuji (tanifuji.shinichi@kobelco.com), K. Yamamoto, H. Fujii, Y.
Kurokawa, Kobe Steel Ltd., Japan
Due to high deposition rate and ability to form hard and dense coating, arc
ion plating (AIP) has been applied in many industrial applications.
Meanwhile, emission of macro-particles (MPs) and delamination of the
coating due to large compressive residual stress are considered as
drawbacks of AIP process. Emission of MPs can be reduced by controlling
the movement of arc spot during the discharge which can be manipulated by
application of external magnetic field. The new arc cathode was developed
through the magnetic field design of the cathode surface. The relationship
between the vacuum arc plasma state and the property of the deposited
various nitride coatings were investigated for conventional and the newly
developed arc cathode. There were three advantages as vacuum arc cathode
for new arc cathode. First, the number of MPs on the coating deposited by
new cathode can be reduced resulting much improved surface morphology.
Yamamoto et al. reported that the improvement of the surface morphology
of the coating deposited by new cathode was correlated with the velocity of
cathode spot on the surface of the target [1] . Second, Although deposition
varies depending on the cathode material, we have observed general
increase in deposition rate in case of the new cathode. Third, the residual
compressive stress of the TiAl(50/50)N coating deposited by new cathode
can be halfed compared to conventional cathode, so it is possible to deposit
the thick coating on the sharp edge of the cutting tool by the new cathode.
To investigate mechanism for these improvements by the new cathode,
optical emission analysis of vacuum arc plasma with conventional and new
cathode was conducted.
[1] K. Yamamoto et al., presented at ICMCTF 2010 at San Diego G6-7
1:50pm B1-2-2 Industrial-scale sputter deposition of Cr1-xAlxN
coatings with various compositions from segmented Cr and Al targets,
T. Weirather (thomas.weirather@unileoben.ac.at), C. Sabitzer, S. Grasser,
Montanuniversität Leoben, Austria, C. Czettl, Ceratizit Austria GmbH,
Austria, P. Polcik, PLANSEE Composite Materials GmbH, Germany, M.
Kathrein, Ceratizit Austria GmbH, Austria, C. Mitterer, Montanuniversität
Leoben, Austria
Over the last 20-25 years, extensive research has been conducted on ternary
MeAlN coatings like TiAlN and CrAlN and their outstanding properties for
wear protection, e.g. in cutting applications. While CrAlN in particular
exhibits high oxidation resistance, TiAlN has the advantage of higher
hardness and a more pronounced age-hardening behaviour. These benefits
are enhanced with increasing AlN content in the solid solution, which is, on
the other hand, limited by a threshold value at which a transition from the
face-centered cubic to the undesired hexagonal wurtzite phase occurs. To
study the structure-property evolution in industrial-scale sputtering systems
over wide compositional ranges requires numerous deposition runs with
several sputter targets if conventional targets with a fixed composition are
applied. To reduce this effort, the use of segmented sputter targets is a
promising concept to cover a broad compositional range at a high resolution
in one single deposition run. In the present study, pairs of triangle-like Cr
and Al targets were developed for an industrial-scale magnetron sputtering
system to produce 1.4 µm thick Cr1-xAlxN hard coatings with various
compositions. They were deposited on 2.1 µm thick TiAlN base layers to
provide constant adhesion to the cemented carbide substrates. The TiAlN
layers were grown from homogeneous TiAl targets with an Al content of 60
at.%; all used targets were produced by powder metallurgical methods.
Energy-dispersive X-ray emission spectroscopy measurements on the
Cr1-xAlxN layers showed AlN contents in the range of 0.21