4. Phase Diagrams

Phase Transformations — Quiz

Test your understanding of phase transformations with 5 practice questions.

Practice Questions

Question 1

Which term in the expression $\Delta G_{\text{total}}=\tfrac{4}{3}\pi r^{3}\Delta G_{v}+4\pi r^{2}\gamma$ corresponds to the interfacial energy contribution?

Question 2

Which condition defines the spinodal region for spontaneous decomposition in a binary alloy?

Question 3

Given the Arrhenius relation $D=D_{0}\exp\left(-\frac{Q}{RT}\right)$ with $D_{0}=1\times10^{-6}\,\mathrm{m^{2}/s}$, $Q=200\,\mathrm{kJ/mol}$, $R=8.314\,\mathrm{J/(mol\,K)}$, and $T=800\,\mathrm{K}$, what is the diffusion coefficient $D$ to one order of magnitude?

Question 4

In diffusional phase transformations, how does increasing undercooling (greater $\Delta T$) typically affect nucleation and growth rates?

Question 5

What is the primary mechanism by which fine coherent precipitates strengthen a metal during age-hardening?