DoITPoMS

Questions

1. Which of the regions of this Fe-C phase diagram are solid solutions?

   

   	a	1, 2, 6, 9
   	b	2, 6, 7, 8, 9, 10
   	c	2, 6, 9
   	d	2, 4, 6, 8, 9
   	e	4, 7, 8, 10
   	f	7, 10
   	g	1, 2, 6, 7, 9, 10

2. Will the following factors affect the extent of solid solubility?

   Yes	No	a	Composition
   Yes	No	b	Temperature
   Yes	No	c	Atomic radii
   Yes	No	d	Crystallographic structure
   Yes	No	e	Electronegativity
   Yes	No	f	Valency
   Yes	No	g	Interaction parameter

3. How might a supersaturated solid solution be formed, using the following phase diagram? α and β are solid solutions.

   

   	a	Quench from T1 to T2 with composition x
   	b	Cool slowly from T1 to T2 with composition x
   	c	Quench from T1 to T2 with composition y
   	d	Cool slowly from T1 to T2 with composition y

4. Which of these will not explain the strengthening of a solid solution?

   	a	Lattice distortion
   	b	Order hardening
   	c	Stress fields
   	d	Interaction with dislocations

5. Which of these is not a feature of exsolution in a solid solution?

   	a	Negative interaction parameter
   	b	Positive enthalpy of mixing
   	c	Formation of A rich and B rich regions
   	d	Increase in short range order