This set of Materials Science Multiple Choice Questions & Answers (MCQs) focuses on “Phase Transformation Kinetics”.
1. How many types of nucleation process are there and what are they?
a) 2 and (fusion and fission)
b) 2 and (Heterogeneous and Homogeneous)
c) 2 and (Heterogeneous and fusion)
d) 4 and (fusion, fission, Heterogeneous and Homogeneous)
2. What reactions come under supercooling?
b) Eutectic and Peritectic
c) Eutectic and Eutectoid
d) Peritectic and Eutectoid
3. What is/are the phenomenon involved in phase transformation?
d) Nucleation and growth
4. What are the characteristics of large supercooling in nucleation?
a) Few nuclei, large crystals
b) Rapid nucleation, many nuclei, small crystals
c) Rapid nucleation, many nuclei, large crystals
d) Few nuclei, small crystals
a) Nucleation rate, over all transformation rate
b) Over all transformation rate, Nucleation rate
c) Nucleation rate, finer grain size
d) Over all transformation rate, finer grain size
6. What does phase transformation involve?
a) Transformation rates kinetics
b) Movement/rearrangement of atoms
c) Changes in microstructure
d) Transformation rate kinetics, rearrangement of Atoms, Changes in microstructure
7. At what temperature does supercooling is needed in homogeneous nucleation?
b) 100- 250°C
8. Which is the most important thermodynamic parameter in Homogenous nucleation?
a) Free energy G
b) Enthalpy H
c) Entropy S
d) Free energy G, Enthalpy H, Entropy S
9. Below the critical radius the tiny particles are _______ and are called _______
a) unstable, grains
b) stable, grains
c) unstable, embryo
d) stable, embryo