Q1: Coarse grained steels have

ANS:B - no tendency to distort

Coarse-grained steels typically exhibit lower toughness compared to fine-grained steels. Here's why:

1. Low Toughness: Coarse-grained steels have larger grains within their microstructure. These larger grains can act as stress concentration points, making the material more prone to crack initiation and propagation, reducing its toughness. In materials science, toughness refers to the ability of a material to absorb energy and plastically deform before fracturing.
2. Distortion Tendency: Coarse-grained steels can indeed have a tendency to distort under certain conditions, especially during heat treatment processes or when subjected to significant thermal or mechanical stresses. The larger grains in coarse-grained steels may lead to non-uniform deformation, which can result in distortion of the material.
3. Density: Grain size does not directly affect the density of steel. Coarse-grained and fine-grained steels can have similar densities since density primarily depends on the chemical composition of the steel rather than its microstructure.
4. Very High Toughness: Coarse-grained steels generally do not exhibit very high toughness. Instead, fine-grained steels are typically engineered to have high toughness by refining the grain size, which helps to inhibit crack propagation and improve resistance to fracture.