Question

Which of the following characteristics of active-passive metal will acquire optimize crevice corrosion resistance?

(a) A narrow active-passive transition

(b) A small critical current density

(c) An extended passive region

(d) A narrow active-passive transition, a small critical current density, and an extended passive region

I got this question during an interview.

Query is from Eight Forms topic in portion Eight Forms of Corrosion of Corrosion Engineering

Answer 1

Correct choice is (d) A narrow active-passive transition, a small critical current density, and an extended passive region

The explanation: The optimum crevice corrosion resistance of active-passive transition metal is acquired by having the following characteristics: i. A narrow active-passive transition

                           ii. A small critical current density

                           iii. An extended passive region