Influence of high velocity oxygen-fuel spraying parameters on the wear resistance of Al–SiC composite coatings deposited on ZE41A magnesium alloy

High velocity oxygen-fuel (HVOF) has been used as fabrication technique to deposit aluminium coatings reinforced with silicon carbide particles on Mg–Zn substrates. The aim of the investigation is to improve the tribological performance of the ZE41A magnesium alloy. The parameters of the thermal spraying system have been optimized in order to maximize the SiC particles incorporation in the aluminium matrix of the coating and to minimize the mechanical deterioration of the light alloy substrate. Pin-on-disc tests were developed to characterize the tribological behavior of the different specimens. Composite coatings with thicknesses of 120 μm, reinforced with ∼10 wt% and with high adhesion to the substrate were achieved. The wear resistance of the substrates was increased and the wear rate decreased in two orders of magnitude respect to that of the bare Mg-alloy after the optimization of the spraying parameters.

► Wear protection of the ZE41 magnesium alloys using Al/SiCp composite coatings.
► HVOF coatings deposited on low melting point magnesium substrates.
► Evaluation of HVOF process parameters to obtain the most wear protective coatings.
► Influence of spraying parameters in the final SiCp content in the coating.
► Wear mechanisms in the coatings and their relation with spraying parameters.