Material Science Quiz (Phase Diagrams)

1. Gibbs phase rule for general system:
(a) P+F=C-1              (b) P+F=C-1             (c) P+F=C-2              (d) P+F=C+2

2. In a single-component condensed system if degree of freedom is zero, maximum number of phases that can co-exist_________.
(a) 0                        (b) l                        (c) 2                        (d) 3

3. The degree of freedom at triple point in unary diagram for water________.
(a) 0                        (b) l                        (c) 2                        (d) 3

4. Above the following line, liquid phase exist for all compositions in a phase diagram, (a) Tie-line               (b) Solvus                (c) Solidus                (d) Liquidus

5. Following is wrong about a phase diagram.
(a) It gives information on transformation rates.
(b) Relative amount of different phases can be found under given equilibrium conditions.
(c) It indicates the temperature at which different phases start to melt.
(d) Solid solubility limits are depicted by it.

6. Not a Hurne-Ruthery condition:
(a) Crystal structure of each element of solid solution must be the same.
(b) Size of atoms of each two elements must not differ by more than 15%.
(c) Elements should form compounds with each other.
(d) Elements should have the same valence.

7. Pick the odd one in the following:
(a) Isoniorphoiis alloy                  
(b) Terminal solid solution
(c) Intermediate solid solution        
(d) Compound

8. The boundary line between (liquid) and (liquid—solid) regions must be part of
(a) Solvus                 (b) Solidus                (c) Liquidus              (d) Tie-line

9. The boundaiy line between (liquid-solid) and (solid) regions must be part of
(a) Solvus                 (b) Solidus                (c) Liquidus              (d) Tie-line

10. The boundary line between (alpha) and (alpha+beta) regions must be part of
(a) Solvus                 (b) Solidus                (c) Liquidus              (d) Tie-line

11. Horizontal arrest in a cooling am? represents:
(a) Continuous cooling          (b) Invariant reaction            (c) Both         (d) None

12. Relative amounts of phases in a region can be deduced using
(a) Phase rule            (b) Lever rule            (c) Either                  (d) None

13. An invariant reaction that produces a solid up on cooling wo liquids:
(a) Eutectic               (b) Peritectic             (c) Monotectic           (d) Syntectic

14. A solid + a liquid result in a liquid up on heating during__________reaction.
(a) Eutectic               (b) Peritectic             (c) Monotectic           (d) Syntectic

15. A solid + a liquid result in a solid up on cooling during__________reaction.
(a) Eutectic               (b) Peritectic             (c) Monotectic           (d) Syntectic

16. On heating, one solid phase results in another solid phase phis on liquid phase during ___reaction.
(a) Eutectic               (b) Peritectic             (c) Monotectic           (d) Syntectic

17. A solid phase results in a solid plus another solid phase up on cooling during __________reaction.
(a) Eutectoid             (b) Peritectoid           (c) Eutectic               (d) Peritectic

18. A solid phase results in a solid plus another solid phase up on heating during __________reaction.
(a) Eutectoid             (b) Peritectoid           (c) Monotectoid         (d) None

19. A liquid phase produces two solid phases during_________reaction up on cooling.
(a)Eutectic               (b) Eutectoid             (c) Peritectic             (d) Peritectoid

20. Liquid phase is involved in die following reaction:
(a) Eutectoid             (b) Peritectoid           (c) Monotectoid        (d) None

21. Not a basic step of precipitation strengthening
(a) Solutionizing        (b) Mixing and compacting   (c) Quenching           (d) Aging

22. Both nucleatiou and growth require change in free energy to be________.
(a) -ve                     (b) zero                    (c) +ve           (d) Any

23. During homogeneous nucleation. critical size of a particle______with increase in
under-cooling.
(a) Increases             (b) Decreases            (c) Won't change       (d) Not related

24. Not a typical site for nucleation during solid state transformation

25 Growth occurs by
(a) Diffusion controlled individual movement of atoms
(b) Diffusion-less collective movement of atoms
(c) Both                          
(d) None

26. Overall transformation rate changes with temperature as follows:
(a) Monotonically decreases with temperature      
(b) First increases, then decreases

(c) Initially it is slow, and then picks-up              
(d) Monotonically increases with temperature

27. wt.% of carbon in mild steels
(a) <0.008                (b) 0.008-0.3             (c) 03-0.8                 (d) 0.8-2.11

28. Eutectic product in Fe-C system is called
(a) Pearlite               (b) Bainite                (c) Ledeburite           (d) Spheroidite

29. Eutectoid product in Fe-C system is called
(a) Pearlite               (b) Bainite                (c) Ledeburite           (d) Spheroidite

30. Phases that exist on left side of an invariant reaction line are called
(a) Pro-phase             (b) Hypo-phase         (c) Hyper-phase         (d) None

31. Alloying element that decreases eutectoid temperature in Fe-C system
(a) Mo                     (b)Si                       (c)Ti                       (d)Ni

32. Nose of a C-curve represents
(a) Shortest time required for specified fraction of transformation
(b) Longest time required for specified fraction of transformation
(c) Average time required for specified fraction of transformation
(d) No information regarding time required for specified fraction of transformation

33. Phase formed of diffusion-less reaction:
(a) Pearlite                (b) Lower Bainite      (c) Upper bainite        (d) Martensite

34. Ms for Fe-C system is round_____C.
(a) 725                     (b)550                     (c)450                     (d)210

35. Impurity uol responsible for tender embritllenient
(a) Sn                      (b) Sb                      (c) Si                       (d) As


Answers:
1.   d
2.   c
3.   a
4.   c
5.   a
6.   c
7.   a
8.   c
9.   b
10. a
11.b
12. b
13. d
14. c
15. b
16. b
17. a
18. b
19. a
20. d
21.b
22. a
23. b
24. a
25. c
26. b
27. b
28. c
29. a
30. c
31. d
32. a
33. d
34. d
35. c

Subscribe

Comments

Popular posts from this blog

Electrical Machines (Three Phase Transformers)

Thermodynamics (Compressible Flow)

Electrical Machines (Special Machines)