Question

Which of the following is/are the purposes of coatings?

(a) To acts as a sacrificial metal

(b) To act as an effective barrier

(c) Either to act as sacrificial metal or to act as an effective barrier

(d) Neither to act as sacrificial metal nor to act as an effective barrier

The question was posed to me in an interview for job.

The query is from Corrosion Prevention in chapter Corrosion Prevention of Corrosion Engineering

Answer 1

The correct option is (c) Either to act as sacrificial metal or to act as an effective barrier

Best explanation: Coatings are the relatively thin material portion on the surfaces of native metal to avoid direct exposure to the corrosive environment. The purpose of coatings is either to act as sacrificial metal or to act as an effective barrier.