Chapter 11.17, Problem 38QP

(a)

To determine

The Brinell hardness for a specimen of 1.13wt%C iron-carbon alloy subjected to the heat treatment,

Cool rapidly to $\text{250°C}\left(480\text{°F}\right)$, hold for ${\text{10}}^{\text{3}}\text{s}$, then quench to room temperature.

(b)

To determine

The Brinell hardness for a specimen of 1.13wt%C iron-carbon alloy subjected to the heat treatment,

Cool rapidly to $\text{700°C}\left(1290\text{°F}\right)$, hold for ${\text{10}}^5\text{s}$, then quench to room temperature.

(c)

To determine

The Brinell hardness for a specimen of 1.13wt%C iron-carbon alloy subjected to the heat treatment,

Cool rapidly to $\text{600°C}\left(1110\text{°F}\right)$, hold for $7\text{s}$, rapidly cool to $\text{450°C}\left(\text{840°F}\right)$, again hold for $\text{4}\text{s}$ then quench to room temperature.