Comparative assessment of the mechanical, tribological, and corrosion properties of Al/SiC/Al2O3 and Al/SiC/TiO2 hybrid composites

Stir-casted aluminium alloy 6061 based composites Al/5SiC (AMC), Al/5SiC/4Al2O3 (AHC1), and Al/5SiC/4TiO2 (AHC2) were evaluated and compared for their mechanical, wear, and corrosion characteristics. The qualities of the composite samples have been assessed using tensile testing, impact testing, micro hardness testing, microstructural analysis, and porosity assessment. The findings show that the hardness and ultimate tensile strength of composites are increased by the addition of 4 wt.% TiO2 and 4 wt.% Al2O3. However, the addition of 4 wt.% Al2O3 slightly decreased the % elongation and impact toughness. Compared to the others, the AHC2 composite performs better in mechanical properties. This composite exhibit balanced impact strength and hardness values. The impact toughness of AHC2 composites is 1.08 times that of AMC and 1.48 times that of AHC1 composites. AHC2 composites have a % elongation that is about 33% greater than that of AMC and 55% greater than that of AHC1 composites. AHC2 composites have a tensile strength that is around 17.4% higher than AMC and 5.1% higher than AHC1 composites. AHC2 composites had specific wear rate (WR) of 1.64 x 10-7 mm3/Nm, which were 1.56 times lower than those of AHC1 composites and 2.35 times lower than those of AMC. The specific WR and frictional coefficient go down when the AHC2 composites become harder and more difficult to break. Because their icorr values are lower than those of AMC composites, AHC1 and AHC2 exhibit greater corrosion resistance. The addition of alumina and titania particles decreases the electrochemically active area and enhanced the strength at interfaces among the reinforcements and matrix, which results in increased corrosion resistance.