TY - JOUR
T1 - Anodisation of sputter deposited aluminium–titanium coatings
T2 - Effect of microstructure on optical characteristics
AU - Aggerbeck, Martin
AU - Junker-Holst, Andreas
AU - Nielsen, Daniel Vestergaard
AU - Gudla, Visweswara Chakravarthy
AU - Ambat, Rajan
PY - 2014/9/15
Y1 - 2014/9/15
N2 - Magnetron sputtered coatings of aluminium containing up to 18 wt.% titanium were deposited on aluminium substrates to study the effect of microstructure on the optical appearance of the anodised layer. The microstructure and morphology were studied using transmission electron microscopy (TEM), X-ray diffraction (XRD), and glow discharge optical emission spectroscopy (GDOES), while the optical appearance was investigated using photospectrometry. The microstructure of the coatings was varied by heat treatment, resulting in the precipitation of Al3Ti phases. The reflectance of the anodised surfaces decreased with titanium content in the as-deposited, and heat-treated states, and after anodisation of the as-deposited coatings. Specimens turned grey or black when anodising after heat treatment. Partially anodised Al3Ti phases were found in the anodised layer, and the interface between substrate and anodised layer was rough, causing light trapping. Progressive darkening of the anodised layer is assumed to be due to the synergetic effect of morphology of incorporated intermetallics and substrate interface.
AB - Magnetron sputtered coatings of aluminium containing up to 18 wt.% titanium were deposited on aluminium substrates to study the effect of microstructure on the optical appearance of the anodised layer. The microstructure and morphology were studied using transmission electron microscopy (TEM), X-ray diffraction (XRD), and glow discharge optical emission spectroscopy (GDOES), while the optical appearance was investigated using photospectrometry. The microstructure of the coatings was varied by heat treatment, resulting in the precipitation of Al3Ti phases. The reflectance of the anodised surfaces decreased with titanium content in the as-deposited, and heat-treated states, and after anodisation of the as-deposited coatings. Specimens turned grey or black when anodising after heat treatment. Partially anodised Al3Ti phases were found in the anodised layer, and the interface between substrate and anodised layer was rough, causing light trapping. Progressive darkening of the anodised layer is assumed to be due to the synergetic effect of morphology of incorporated intermetallics and substrate interface.
KW - Aluminium
KW - Titanium
KW - Anodisation
KW - Microstructure
KW - Appearance
KW - TEM
U2 - 10.1016/j.surfcoat.2014.05.073
DO - 10.1016/j.surfcoat.2014.05.073
M3 - Tidsskriftartikel
SN - 0257-8972
VL - 254
SP - 138
EP - 144
JO - Surface and Coatings Technology
JF - Surface and Coatings Technology
ER -