Corrosion behaviour of MoSx-based coatings deposited onto high speed steel by magnetron sputtering
Autor: | H. Kappl, Martin Balzer, Alan Savan, Martin Fenker |
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Rok vydání: | 2006 |
Předmět: |
Materials science
Scanning electron microscope Metallurgy Surfaces and Interfaces General Chemistry Sputter deposition engineering.material Condensed Matter Physics Surfaces Coatings and Films Corrosion Coating Sputtering Physical vapor deposition Cavity magnetron Materials Chemistry engineering High-speed steel |
Zdroj: | Surface and Coatings Technology. 201:4099-4104 |
ISSN: | 0257-8972 |
Popis: | MoSx-based films were deposited using magnetron sputtering from a pure MoS2 target. Alloying was accomplished by “co-deposition” from separate targets onto substrates having a two-fold rotation. An additional experiment had also a Cr+-ion etch for surface preparation, followed by a Cr adhesion layer, made using a Cr target mounted on a cathodic arc evaporation source. MoSx and Al- and Ti-alloyed MoSx coatings have been deposited onto high speed steel (HSS) and glass substrates for corrosion investigations. The coatings were characterised by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, hardness and adhesion measurements. The corrosion behaviour of the samples was electrochemically measured by open-circuit-potential (OCP) measurements and by potentiodynamic corrosion tests in 0.8 M NaCl solution (pH 7). Additionally the MoSx-based coatings on HSS have been exposed to salt spray tests. The corrosion investigations revealed that the addition of Al and Ti to MoSx shifts the open-circuit-potential of about 80 to 110 mV to lower values, i.e. the alloying elements make the MoSx coating a little bit less noble. In agreement with the OCP measurements, the corrosion potential Ecorr in potentiodynamic corrosion tests was the highest for non-alloyed MoSx coatings on HSS substrates. After the potentiodynamic corrosion tests, a strong corrosive attack could be observed for all coated samples. In salt spray tests the lowest number of corrosion pits was found for the MoSx–Al (Cr+) coating on HSS. |
Databáze: | OpenAIRE |
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