Question 222General Subjects - Assistant Engineer

70% to pass

When a low carbon steel is undergoing heat treatment for the purposes of casehardening, what is the process that distinguishes this procedure from other hardening methods?

AAfter the steel is heated above its critical temperature, it is quenched in a carbon bath.
BAfter the steel is heated above its critical temperature, it is quenched in cold water.
CAfter the steel is heated above its critical temperature, it is allowed to cool slowly in air.
DAfter the steel is heated above its melting temperature, it is quenched in a carbon bath.
AI Explanation

The correct answer is A) After the steel is heated above its critical temperature, it is quenched in a carbon bath. This is the correct answer because the process of casehardening involves heating the steel above its critical temperature, then quenching it in a carbon-rich environment, such as a carbon bath. This allows carbon to diffuse into the surface of the steel, creating a hard, wear-resistant case while maintaining a softer, more malleable core. The other options, such as quenching in water or slow cooling in air, do not result in the characteristic carbon diffusion that defines the casehardening process.

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