Quiznetik

Material Science | Set 3

1. the and property of metals increase due to cold working

Correct : C. electrical resistance, internal stresses

2. the and property of metals decrease due to cold working

Correct : D. corrosion resistance, ductility

3. the property of metals increases and property decreases due to cold working

Correct : A. hardness, electrical conductivity

4. the process by which the internal stresses are reduced in cold worked metal is called

Correct : C. heat treatment

5. the heat treatment which is used to reduce the internal stresses after cold working is called as

Correct : B. annealing

6. during recovery part of annealing treatment, which of the following properties are improved noticeably?

Correct : D. internal stresses, electrical resistance, corrosion resistance

7. during which stage of annealing there is no major change in microstructure ?

Correct : B. recovery

8. the process of formation of new grains starts by the process of

Correct : B. nucleation

9. nucleation starts at areas of

Correct : B. high energy

10. new grain formation take place in stage of annealing treatment

Correct : C. recrystalliza tion

11. after the recrystalllization stage

Correct : D. all of the above

12. during grain growth takes place

Correct : C. larger grains are formed

13. strain hardening followed by annealing is known as

Correct : B. hot working

14. there are no residual internal stresses after hot working because

Correct : C. there is simultaneou s working and recrystalliza tion

15. wire drawing is a type of

Correct : A. cold working

16. hot forging is a type of

Correct : B. hot working

17. in working of metals, the microstructure is distorted

Correct : B. cold

18. it is possible to continuosly work on metal during working

Correct : A. hot

19. cold working requires higher than hot working

Correct : C. energy for plastic deformation

20. the possibility of oxidation is higher in case of working of metals

Correct : A. hot

21. in case of hot working of metals, there is higher possibility of

Correct : C. both a and b

22. the machinery used for hot working is than used for cold working

Correct : C. same

23. the resolved shear stress of a unit cell in nickel is N/mm2 if a tensile stress of 13.7 Mpa is applied. Take angle between the axial force and slip direction is 450 and angle between axial force and normal to slip is 540

Correct : B. 5.7

24. if resolved shear stress is maximum, it is given by

Correct : D. 0.5σt

25. at 450 the resolved shear stress is

Correct : B. maximum

26. this is type of slip systems.

Correct : A. glide

27. it is type of stacking faults

Correct : D. intrisic

28. get for burger vector

Correct : C. direction

29. is defined as fraction of volume occupied by atoms in unit cell

Correct : C. atomic packing number

30. A crystalline material must have

Correct : C. repetitive arrangement of atoms in all three direction

31. A family of directions is represented by

Correct : B. <uvw>

32. A hexagonal crystal system consists of

Correct : D. both b & c

33. A higher value of atomic packing factor number indicates

Correct : D. both b & c

34. A higher value of co-ordination number indicates

Correct : B. higher density of material

35. A material having repetitive arrangement of atoms over larger atomic distances is called

Correct : A. crystalline material

36. A non-crystalline material is characterized as having _

Correct : B. repetitive arrangement of atoms in any one direction

37. A single cubic crystal system consists of

Correct : D. both a & c

38. A unit cell represents of a crystal structure

Correct : C. geometry

39. APF (Atomic Packing Factor) of Body- Centered Cubic structure is…..

Correct : C. 0.68

40. FCC structure have APF (Atomic Packing Factor) of …..

Correct : A. 0.74

41. HCP structure have APF (Atomic Packing Factor) of …..

Correct : A. 0.74

42. Atomic packing factor is

Correct : C. volume fraction of atoms in cell

43. Average frequency of atomic vibrations in a solid (in Hz)

Correct : D. 10+13

44. BCC have Average no. of atoms per unit cell

Correct : B. 2

45. BCC have ligancy number

Correct : D. 8

46. BCC having stacking

Correct : C. abababa b

47. Beneficial property of foreign particles

Correct : C. obstructs dislocation motion

48. Burger vector gives of the shift

Correct : A. amount

49. Burger vector to dislocation line is for edge dislocations

Correct : B. parallel

50. Carbon diffuses in Fe, this is type of impurity

Correct : B. interstitial

51. Cold working process is carried out on ……….. Recrystallisation temp.

Correct : C. below

52. Coordination number for closest packed crystal structure

Correct : B. 12

53. Coordination number in simple cubic crystal structure

Correct : B. 6

54. Coordination Number of Body-Centered Cubic structure is…..

Correct : B. 8

55. Ligancy of FCC structure are…..

Correct : D. 12

56. HCP structure have ligancy …..

Correct : D. 12

57. Crystal structure is arrangement of in different patterns

Correct : C. atoms

58. Crystallographic planes are represented by 3 numbers enclosed in

Correct : C. ( ) raound bracket

59. crystallography is study of

Correct : C. different pattern formation of atoms

60. Cu diffuses in FCC Ni, this is type of impurity

Correct : A. substitution al

61. Decrease in free energy during recovery is attributed to

Correct : A. excess point defects

62. Decrease in free energy during recrystallization is attributed to

Correct : B. excess dislocations

63. Deformation of steel at room temperature is

Correct : B. cold working

64. Density of material depends on …..

Correct : D. both a&b

65. Dimensional accuracy is better in

Correct : B. cold working

66. Dislocations have types

Correct : C. 3

67. Example for strengthening mechanism in single-phase material

Correct : A. strain hardening

68. FCC crystal having crystal systems.

Correct : A. 12

69. FCC have Average no. of atoms per unit cell

Correct : C. 4

70. FCC have ligancy number

Correct : B. 12

71. FCC having atomic packing factor

Correct : C. 0.74

72. FCC having stacking

Correct : A. abcabca bc

73. FCC materials are good in ….

Correct : C. ductile

74. Figure out the odd one in the following

Correct : A. frenkel defect

75. Fine grain size, usually, can not be obtained during the following process

Correct : A. slow cooling

76. Following strengthening mechanism applies to multi-phase material

Correct : B. dispersion hardening

77. Forces required in cold working is than hot working

Correct : A. greater

78. Frenkel defect have missing of

Correct : A. cation

79. Good surface finish in................ process

Correct : A. cold working

80. grain boundaries the dislocation motion

Correct : B. restricts

81. Grain boundaries decides                          of dislocations that can move

Correct : A. lenghts

82. Handling is difficult in

Correct : A. hot working

83. Hardness during over-aging

Correct : A. decreases

84. HCP have Average no. of atoms per unit cell

Correct : A. 6

85. HCP having atomic packing factor

Correct : C. 0.74

86. Lower the degree of deformation, recrystallization temperature is

Correct : B. lower

87. Higher the degree of deformation, recrystallization temperature is

Correct : A. higher

88. Hot working process is carried out on ……….. Recrystallisation temp.

Correct : B. above

89. If the deformation is carried at 0°C, it is

Correct : D. can’t say

90. If the deformation is carried at 100°C, it is

Correct : D. can’t say

91. If the deformation is carried at 500°C, it is

Correct : D. can’t say

92. If the deformation is carried out above RCT, it is

Correct : B. hot working

93. If the deformation is carried out below RCT, it is

Correct : A. cold working

94. In BCC, the lattice parameter (a) is

Correct : A. (4/√3) r

95. In case of polycrystalline materials regeneration rate of dislocations

Correct : A. increases

96. In climb, the dislocation moves of the surface

Correct : B. out, glide

97. In Cold work,strength

Correct : A. increases

98. In cold working, corrosion resistance

Correct : B. decreases

99. In cold working, due to strain hardening ductility of metal

Correct : B. decreases

100. In cold working, electrical resistance

Correct : A. increases