Question

Which of the following metal combination has a minimum galvanic effect?

(a) Monel and copper

(b) Inconel (passive) and Inconel (active)

(c) 18-8 stainless steel (active) and 18-8 stainless steel (passive)

(d) Titanium and lead

The question was asked during an interview.

My question is taken from Eight Forms topic in chapter Eight Forms of Corrosion of Corrosion Engineering

Answer 1

The correct choice is (a) Monel and copper

For explanation: The galvanic effect can be reduced by selecting close metal combinations. The position of a metal or an alloy in galvanic is mainly affected by its composition and its state (active or passive). Monel (70 Ni, 30Cu) and copper is the close metal combination, hence it has a minimum galvanic effect.