Effect of varying weight fraction of silicon carbide (SiCp) particles on the corrosion resistance of Al–Zn–Mg–Cu/SiCp composite

Abstract

ABSTRACT Metal corrosion is a significant economic issue, affecting 4–5% of GDP. Aluminium and its alloys are moderately resistant to corrosion but become vulnerable in chloride ion environments. Ceramic particles can be incorporated to reduce corrosion, as ceramics are inactive in the corrosive medium. So, the present work investigates the effect of ceramic particle (SiCp) variation in the Al–Zn–Mg–Cu alloy on corrosion resistance. Experimental data reveals that incorporating silicon carbide particles would enhance the corrosion resistance over monolithic alloys. Open circuit potential (OCP) shows that changes in OCP values from −0.8134 V (Al7075S00) to −0.7484 V (Al7075S20) towards the noble direction with increasing the weight per cent of SiCp. The potentiodynamic polarisation (PDP) curve discloses the lowest I corr values for Al7075S20. In the Nyquist plot, the diameter of the capacitive loop increases with increasing the SiCp content; Al7075S20 shows a higher capacitive loop. Overall, the outcomes of the Nyquist, Bode and Tafel plots show good agreement regarding the findings.