A Comparative Study of Corrosion Behavior of Al/SiCp Composite with Cast Iron

Abstract

Corrosion behavior of LM13 aluminum alloy/silicon carbide particle (SiCp) composite was compared with that of cast iron in three different corrosive media (i.e., mine water, 3.5% sodium chloride [NaCl] solution, and 3.5% sodium hydroxide [NaOH] solution) through the immersion technique. It has been noted that the composite exhibits significantly higher corrosion resistance than cast iron in NaCl solution (marine) and mine water. However, it suffers from higher corrosion rates than cast iron in NaOH solutions. In fact, in NaOH solution, cast iron exhibits insignificant corrosion rates. It has been observed further that the composite exhibits minimum corrosion rates in NaCl media and maximum rates in NaOH solution. Cast iron, however, suffers from the highest corrosion rate in mine water and the least in NaOH solution. In all environments, the corrosion rate of the materials starts reducing after a specific time and finally reaches a stable value. The corroded surfaces of these materials have been studied through scanning electron microscopy and x-ray diffraction, and the mechanism of material removal has been proposed.

Erosive–corrosive wear of aluminum alloy composites: Influence of slurry composition and speed

“…Previous research confirmed the formation of a stable Al 2 O 3 passive film in NaCl [43]. On the other hand, when Al alloys Fig.…”

“…Further, the crevices formed at these discontinuities allowed the corrodant to enter the composite making them relatively more susceptible to corrosion. However, the reduction in the effective metallic area exposed to corrodant due to the dispersion of SiC in metallic surface, restricts the growth of pits as reported previously [43]. These two effects counteracted and marginally vary the wear resistance of the composite from that of the alloy when the slurry consists of no suspended particles.…”

Erosive wear response of SiCp reinforced aluminium based metal matrix composite: Effects of test environments

“…Moreover in the case of a basic environment, corrosion was the uppermost mechanism of wear although damaged SiC particles and minor cracks were also detected on the surface. This is because of the severe corrosive attack due to the formation of AlO2 -ions in the basic solution that led to the dissolution of the primary dendrites of Al leaving behind the Si/precipitate network [39].…”

Erosion-corrosion behavior of SiC particle-reinforced Al-Si alloy in NaOH slurry

“…[6] In other words, no stable passive layer forms on the surface of the Al alloy and composites, in basic environments; hence, they experienced greater corrosive attack in NaOH media. Addition of sand particles to NaOH media (pH ϭ 11.5) decreased in the effective volume of the corrodant.…”

“…It is reported that AMCs and their matrix alloys experienced greater corrosive attack in NaOH media than in acidic and marine media. [6] Few studies have been done to evaluate the erosion-corrosion behavior of AMCs in synthetic mine water. [7,9] These studies indicated that AMCs exhibited better performance in erosive-corrosive conditions than their matrix alloys in contrast to their performance in corrosive atmospheres such as marine and acidic environments.…”