Investigation of exposure interval on the corrosion activities of Al 6061 hybrid nanocomposite in the acidic immersion corrosion experiment

This learning optimized corrosion determinant for Corrosion Rate (CR) of Aluminum (Al) 6061 base matrix alloy, strengthened by 0.6 wt.% Silicon Carbide (SiC) in addition with 0.2 wt.% Boron Carbide (B₄C) hybrid nano Metal Matrix Composite (MMC) manufactured using ultrasonic-aided stir casting. Nanoparticles raised the density of the Al 6061 alloy from 2.687 to 2.698 g/cm3. The Vicker’s microhardness for hybrid nano MMC was 63.795 HV, which is 18% greater than the base raw Al 6061 alloy. The metallurgical investigation confirmed the presence and dispersion of green variety of SiC and higher hardness B₄C nanoparticles in the MMC, which produced intermetallic phases. Corrosion performance was evaluated in Sulphuric acid (H2SO2), Nitric acid (HNO3) and Hydrochloric acid (HCl) acidic media at fluctuating dipping periods using a Taguchi L9 orthogonal array. Results showed that dipping durations and acid type significantly influenced the CR. The CR was uppermost in HCl and diminished with longer soaking due to passive layer formation.