Question

__________ can be added to steels to prevent intergranular failure.

(a) Sulfur

(b) Manganese

(c) Silicon

(d) Wood

The question was asked at a job interview.

Question is from Fracture Toughness, Protection against Fracture in section Imperfection in Metal Crystals, Fracture, Corrosion and Oxidation of Engineering Material & Metallurgy

Answer 1

Right option is (b) Manganese

For explanation I would say: Intergranular failure occurs due to the continuous brittle phase at the boundary. In steels, the presence of sulfur creates a brittle iron sulfide film. This can be prevented by the addition of manganese in steel.