LIC ADO - Engineering Materials 1000+ MCQ [Solved] PDF Download

1. Admiralty gun metal contains
A. 63 to 67% nickel and 30% copper
B. 88% copper, 10% tin and rest zinc
C. Alloy of tin, lead and cadmium
D. Iron scrap and zinc
Answer : B

2. Manganese is added in low carbon steel to
A. Make the steel tougher and harder
B. Raise the yield point
C. Make the steel ductile and of good bending qualities
D. All of the above
Answer : C

3. Chilled cast iron has
A. No graphite
B. A very high percentage of graphite
C. A low percentage of graphite
D. Graphite as its basic constituent of composition
Answer : A

4. The electric process of steel making is especially adapted to
A. Alloy and carbon tool steel
B. Magnet steel
C. High speed tool steel
D. All of these
Answer : D

5. Process of Austempering results in
A. Formation of bainite structure
B. Carburised structure
C. Martenistic structure
D. Lamellar layers of carbide distributed throughout the structure
Answer : A

6. In malleable iron, carbon is present in the form of
A. Cementite
B. Free carbon
C. Flakes
D. Nodular aggregates of graphite
Answer : D

7. Malleable cast iron
A. Contains 1.7 to 3.5% carbon in Free State and is obtained by the slow cooling of molten cast iron
B. Is also known as chilled cast iron and is obtained by cooling rapidly. It is almost unmachinable
C. Is produced by annealing process. It is soft, tough, and easily machined metal
D. Is produced by small additions of magnesium (or cerium) in the ladle. Graphite is in the nodular or spheroidal form and is well dispersed throughout the material
Answer : C

8. The ratio of the volume occupied by the atoms to the total volume of the unit cell is called
A. Coordination number
B. Atomic packing factor
C. Space lattice
D. None of these
Answer : B

9. In nodular iron, graphite is in the form of
A. Cementite
B. Free carbon
C. Flakes
D. Spheroids
Answer : D

10. The tensile strength of wrought iron is maximum
A. Along the lines of slag distribution
B. Perpendicular to lines of slag distribution
C. Uniform in all directions
D. None of the above
Answer : A

11. The percentage of carbon in grey iron castings usually varies between
A. 0.5 to 1 %
B. 1.2 %
C. 2.5 to 4.5 %
D. 5 to 7 %
Answer : C

12. Eutectoid steel contains following percentage of carbon
A. 0.02 %
B. 0.3 %
C. 0.63 %
D. 0.8 %
Answer : D

13. Which is false statement about tempering? Tempering is done to
A. Improve machinability
B. Improve ductility
C. Improve toughness
D. Release stresses
Answer : A

14. Steel with ________ carbon is known as hypo-eutectoid steel.
A. 0.8 %
B. Below 0.8 %
C. Above 0.8 %
D. None of these
Answer : B

15. For a steel containing 0.8% carbon
A. There is no critical point
B. There is only one critical point
C. There are two critical points
D. There can be any number of critical points
Answer : B

16. Elinvar, an alloy used in precision instruments, hair springs for watches, etc. contains the following element as principal alloying element
A. Iron
B. Copper
C. Aluminium
D. Nickel
Answer : D

17. Duralumin contains
A. 94% aluminium, 4% copper and 0.5% Mn, Mg, Si and Fe
B. 92.5% aluminium, 40% copper, 2% nickel, and 1.5% Mg
C. 10% aluminium and 90% copper
D. 90% magnesium and 9% aluminium with some copper
Answer : A

18. Hardness of upper bainite (acicular structure) is about
A. RC 65
B. RC 48
C. RC 57
D. RC 80
Answer : B

19. Large forgings, crank shafts, axles normally contain carbon up to
A. 0.05 to 0.20 %
B. 0.20 to 0.45 %
C. 0.45 to 0.55 %
D. 0.55 to 1.0 %
Answer : C

20. The alloy used for making electrical resistances and heating elements is
A. Nichrome
B. Invar
C. Magnin
D. Elinvar
Answer : A

21. The alloy, mainly used for corrosion resistance in stainless steels is
A. Silicon
B. Manganese
C. Carbon
D. Chromium
Answer : D

22. The lower critical temperature
A. Decreases as the carbon content in steel increases
B. Increases as the carbon content in steel increases
C. Is same for all steels
D. Depends upon the rate of heating
Answer : C

23. Monel metal contains
A. 63 to 67% nickel and 30% copper
B. 88% copper and 10% tin and rest zinc
C. Alloy of tin, lead and cadmium
D. Malleable iron and zinc
Answer : A

24. In full annealing, the hypo eutectoid steel is heated from 30°C to 50°C above the upper critical temperature and then cooled
A. In still air
B. Slowly in the furnace
C. Suddenly in a suitable cooling medium
D. Any one of these
Answer : B

25. Addition of lead and bismuth to aluminium results in
A. Improvement of casting characteristics
B. Improvement of corrosion resistance
C. One of the best known age and precipitation hardening systems
D. Improving machinability
Answer : D

26. Taps dies and drills contain carbon
A. Below 0.5 %
B. Below 1 %
C. Above 1 %
D. Above 2.2 %
Answer : C

27. The percentage of carbon in cast iron varies from
A. 0.1 to 0.5
B. 0.5 to 1
C. 1 to 1.7
D. 1.7 to 4.5
Answer : D

28. An alloy steel which is work hardenable and which is used to make the blades of bulldozers, bucket wheel excavators and other earth moving equipment contain iron, carbon and
A. Chromium
B. Silicon
C. Manganese
D. Magnesium
Answer : C

29. Beryllium bronze has
A. High yield point
B. High fatigue limit
C. Both (A) and (B)
D. None of these
Answer : C

30. A reversible change in the atomic structure of steel with corresponding change in the properties is known as
A. Molecular change
B. Physical change
C. Allotropic change
D. Solidus change
Answer : C

31. The purpose of heat treatment is to
A. Relieve the stresses set up in the material after hot or cold working
B. Modify the structure of the material
C. Change grain size
D. Any one of these
Answer : D

32. In which of the following cases, consideration of creep is important
A. Flywheel of steam engine
B. Cast iron pipes
C. Cycle chains
D. Gas turbine blades
Answer : D

33. Paramagnetic alpha iron changes to gamma iron at
A. 770°C
B. 910°C
C. 1440°C
D. 1539°C
Answer : B

34. Induction hardening is the process of
A. Hardening surface of work-piece to obtain hard and wear resistant surface
B. Heating and cooling rapidly
C. Increasing hardness throughout
D. Inducing hardness by continuous process
Answer : A

35. Cobalt in steel
A. Improves wear resistance, cutting ability and toughness
B. Refines grain size and produces less tendency to carburisation, improve corrosion and heat resistant proper ties
C. Improves cutting ability and reduce hardenability
D. Gives ductility, toughness, tensile strength and anti corrosion property
Answer : C

36. Iron is
A. Paramagnetic
B. Ferromagnetic
C. Ferroelectric
D. Dielectric
Answer : B

37. The aluminium alloy, mainly used, for anodized utensil manufacture, is
A. Duralumin
B. Y-alloy
C. Magnalium
D. Hindalium
Answer : D

38. Maximum percentage of carbon in ferrite is
A. 0.025 %
B. 0.06 %
C. 0.1 %
D. 0.25 %
Answer : A

39. The maximum internal diameter of a blast furnace is about
A. 3 m
B. 6 m
C. 9 m
D. 12 m
Answer : C

40. Wrought iron is
A. Hard
B. High in strength
C. Highly resistant to corrosion
D. Heat treated to change its properties
Answer : C

41. Which of the following constituents of steels is softest and least strong?
A. Austenite
B. Pearlite
C. Ferrite
D. Cementite
Answer : C

42. In a hardening process, the hypo-eutectoid steel is
A. Heated from 30°C to 50°C above the upper critical temperature and then cooled in still air
B. Heated from 30°C to 50°C above the upper critical temperature and then cooled suddenly in a suitable cooling medium
C. Heated from 30°C to 50°C above the upper critical temperature and then cooled slowly in the furnace
D. Heated below or closes to the lower critical temperature and then cooled slowly
Answer : B

43. A material is known as allotropic or polymorphic if it
A. Has a fixed structure under all conditions
B. Exists in several crystal forms at different temperatures
C. Responds to heat treatment
D. Has its atoms distributed in a random pattern
Answer : B

44. Grey cast iron
A. Contains 1.7 to 3.5% carbon in Free State and is obtained by the slow cooling of molten cast iron
B. Is also known as chilled cast iron is obtained by cooling rapidly. It is almost unmachinable
C. Is produced by annealing process. I is soft, tough and easily machined metal
D. Is produced by small additions o magnesium (or cerium) in the ladle Graphite is in nodular or spheroidal form and is well dispersed throughout the material
Answer : A

45. Coarse grained steel
A. Is less tough and has a greater tendency to distort during heat treatment
B. Is more ductile and has a less tendency to distort during heat treatment
C. Is less tough and has a less tendency to distort during heat treatment
D. Is more ductile and has a greater tendency to distort during heat treatment
Answer : A

46. Following elements have face-centred cubic structure
A. Gamma iron (910° to 1400°C), Cu, Ag, Au, Al, Ni, Pb, Pt
B. Mg, Zn, Ti, Zr, Br, Cd
C. A iron (below 910°C and between 1400 to 1539°C), W
D. All of the above
Answer : A

47. The crystal of alpha iron is
A. Body centered cubic
B. Face centered cubic
C. Hexagonal close packed
D. Cubic structure
Answer : A

48. Which of the following represents the allotropic forms of iron?
A. Alpha iron, beta iron and gamma iron
B. Alpha iron and beta iron
C. Body centred cubic iron and face centred cubic iron
D. Alpha iron, gamma from and delta iron
Answer : D

49. Isotropic materials are those which have the same
A. Elastic properties in all directions
B. Stresses induced in all directions
C. Thermal properties in all directions
D. Electric and magnetic properties in all directions
Answer : A

50. The unique property of cast iron is its high
A. Malleability
B. Ductility
C. Surface finish
D. Damping characteristics
Answer : D