Influence of r-GO addition on enhancement of corrosion and wear behavior of AZ31 MMC

In this research, magnesium-based metal matrix composite (MMC) is fabricated through a novel powder metallurgy route, in which synthesized r-GO (reduced graphene oxide) nanosheet at different weight percentages (wt%) is used as reinforcement. The microstructural characterization along with X-ray mapping revealed the appropriate dispersion of r-GO nanosheets into Mg matrix. Effect of r-GO addition on wear loss is studied under drysliding condition with constant influencing parameter and electrochemical corrosion behavior of developed MMC is studied at 3.5% NaCl solution. The addition of r-GO improves the hardness value up to 64 HV, likewise wear loss of MMC decreases up to 0.38 g with respect to r-GO addition. Formation of tribolayer over worn out surface is visualized by means of SEM micrographs. Even though the addition of r-GO improvises the wear behavior, the corrosion resistance of MMC reduces after a certain level of r-GO addition; Mg composites with 0.3 wt% of r-GO depicts low corrosion rate of 3.57 x 10(-7) mpy and further addition of r-GO results in increment in their corrosion rate (4.07 x 10(-5) mpy). Investigation over the SEM micrographs on corroded surface marked the occurrence of galvanic corrosion.