Question

The magnetic properties of steel are greatly affected if the percentage content of manganese exceeds about ___________

(a) 0.1

(b) 0.2

(c) 0.25

(d) 0.3

This question was addressed to me in an interview.

The origin of the question is Steel in portion Steel, Timber, Mortar, Plastics, Non-Ferrous Metals and Alloys of Construction & Building Materials

Answer 1

The correct answer is:

(d) 0.3

The magnetic properties of steel are significantly affected when the percentage of manganese exceeds about 0.3%. Higher manganese content can reduce the steel's magnetic permeability and increase its hardness.