The İnternational Conference on Materials Science, Machine and Automotive Engineerings and Technology, İzmir, Türkiye, 10 - 12 Nisan 2018, ss.573
Magnesium and its alloys are attractive lightweight materials for the applications of aerospace,
chemistry, biomedical, automotive, electronic, and communication industries. Although, magnesium
and its alloys exhibit low density and high strength/weight ratio, their applications are broadly limited
due to their very low corrosion resistance especially in the environments which contain chloride ions
and poor wear resistance. To overcome these limitations, various surface modifications and coatings
are applied on magnesium-based components. Micro-arc oxidation (MAO) method is a promising
surface modification method used to generate thick and compact oxide layers on lightweight materials
such as aluminum, magnesium and titanium without generating extensive heat input in the material.
Particularly MAO coatings enhance wear and corrosion resistance of magnesium-based alloys
drastically.
In the present study, aluminum matrix aluminum oxide (alumina) reinforced composite coating is
produced by cold spraying (CS) on WE43 magnesium alloy, which is a high strength magnesium based alloy offering good mechanical properties both at ambient and elevated temperatures. CS’ed
WE43 magnesium alloy later treated by micro-arc oxidation process in order to obtain a protective
alumina layer. After producing MAO coating on CS’ed surface, cross-section of examined sample was
investigated by optical (OM) and scanning electron (SEM) microscopes. Phase composition of the
layers was determined by the X-ray diffraction (XRD) analysis. Furthermore, hardness measurements
and wear tests were performed to mechanically characterize the samples. To compare the wear
performance of MAO coating and substrate, friction coefficient curves and wear losses were
evaluated.