Corrosion behaviour analysis of SI engine components for ethanol-gasoline blends in flex fuel vehicular application

Corrosion behaviour of ethanol, commercial gasoline and their blends on spark ignition (SI) engine components are investigated by a static immersion test. The experiments are conducted with different concentrations of ethanol in gasoline for different immersion duration at room temperature. The metal specimen and test fuel qualities are inspected to understand insights into the corrosion mechanism. In addition, the changes in surface morphology and elemental composition due to corrosion attacks on the metal specimens are investigated. Further, the nature of oxide formation on the metal surfaces is explored. Moreover, the influence of corrosion products on the physicochemical properties of test fuels is examined. The results exhibit that the percentage of ethanol increases the corrosiveness of test fuels subjected to metal specimens. Also, the existence of oxygen in ethanol plays a significant role in increasing metal corrosion attacks. However, corrosion attack on metal specimens exposed to E100 is higher and significant changes are noticed in the surface characterization at end of the immersion test. Similarly, the physicochemical properties of E100 have a higher variation among test fuels. Finally, this study exhorts some recommendations from the experimental results to mitigate the corrosion behaviour of flex-fuel engine (FFE) components.