Question

Which of these is not a way to prevent intergranular corrosion?

(a) Reduction of carbon level

(b) Quenching

(c) Addition of carbide forming elements

(d) Reduction of alloying elements

I have been asked this question during an interview.

This interesting question is from Corrosion and Oxidation Control in section Imperfection in Metal Crystals, Fracture, Corrosion and Oxidation of Engineering Material & Metallurgy

Answer 1

The correct option is (d) Reduction of alloying elements

For explanation: Improper heat treatment of 18/8 stainless steel may result in intergranular corrosion. It can be prevented by the shrinking of carbon level to less than 0.05%, quenching from high temperature, and the addition of strong carbide forming elements to the steel.