TITLE:
The Effect of Tightening on the Corrosion Properties of the PVD Layers on Magnesium AZ91D Alloy
AUTHORS:
Janusz Kaminski, Michał Tacikowski, Agnieszka Brojanowska, Beata Kucharska, Tadeusz Wierzchon
KEYWORDS:
Magnesium Alloys, Titanium Nitride, PVD Layers, Tightening, Corrosion Resistance
JOURNAL NAME:
Journal of Surface Engineered Materials and Advanced Technology,
Vol.4 No.5,
August
15,
2014
ABSTRACT:
The corrosive
properties of PVD TiN-Ti-Al type composite titanium nitride layer with titanium
and aluminium sub-layers system on the AZ91D magnesium alloy and its sub-layers
were investigated by using polarization method and impedance spectroscopy,
specifically, in terms of the hydrothermal tightening effect. The aim was to
explain the mechanisms which contribute to high anticorrosive properties
obtained by hydrothermal tightening. It was stated that the hydrothermal
treatment changes the surface topography of the examined layers, most probably
due to the formation of a continuous titanium oxides film. Tightening
significantly modifies the corrosion resistance of the particular component
sub-layers of the TiN-Ti-Al layer which exhibits optimum electrochemical
parameters. It was shown that the increase of the electrochemical parameters is
controlled by tightening of the outside titanium nitride layer, whereas the
aluminium sub-layer plays a critical role in creating proper conditions for the
hydrothermal tightening of titanium nitride.