Question

Which of the following is/are the difference between the crevice and pitting corrosion?

(a) Autocatalytic nature

(b) Corrosion mechanism

(c) Initiation method

(d) Both the corrosion mechanism and initiation method

I have been asked this question in an interview for internship.

The query is from Eight Forms topic in division Eight Forms of Corrosion of Corrosion Engineering

Answer 1

Correct choice is (c) Initiation method

The best I can explain: Pitting is a special case of crevice corrosion. But in the view of the initiation method, these two-corrosion processes are different. Pitting corrosion is a self-initiating corrosion form, whereas crevice corrosion needs the formation of crevice (a small gap) with differential concentration from outside.