RRB NTPC - Engineering Materials 1000+ MCQ [Solved] PDF Download

1. Inconel is an alloy of
A. Nickel, chromium and iron
B. Nickel, copper
C. Nickel, Chromium
D. Nickel, zinc
Answer : A

2. Permalloy is a
A. Kind of stainless steel
B. None ferrous alloy
C. Polymer
D. Nickel and iron alloy having high permeability
Answer : D

3. Which of the following when used in ordinary low carbon steels, makes the metal ductile and of good bending qualities?
A. Sulphur
B. Phosphorus
C. Manganese
D. Silicon
Answer : C

4. Which of the following iron exist between 910°C and 1403°C?
A. ?-iron
B. ?-iron
C. ?-iron
D. ?-iron
Answer : C

5. The lower critical point for all steels is
A. 600°C
B. 700°C
C. 723°C
D. 913°C
Answer : C

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

7. Which of the following metal is used in making electrical resistance wire for electric furnaces and heating elements?
A. Babbitt metal
B. Monel metal
C. Nichrome
D. Phosphor bronze
Answer : C

8. The blade of a power saw is made of
A. Boron steel
B. High speed steel
C. Stainless steel
D. Malleable cast iron
Answer : B

9. Balls for ball bearings are made of
A. Cast iron
B. Mild steel
C. Stainless steel
D. Carbonchrome steel
Answer : D

10. Weld decay is the phenomenon found with
A. Cast iron
B. Mild steel
C. Nonferrous materials
D. Stainless steel
Answer : D

11. A cold chisel is made of
A. Mild steel
B. Cast iron
C. HSS
D. High carbon
Answer : D

12. White cast iron has
A. Carbon in the form of carbide
B. Low tensile strength
C. High compressive strength
D. All of these
Answer : D

13. 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

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

15. Which of the following has highest specific strength of all structural materials?
A. Magnesium alloys
B. Titanium alloys
C. Chromium alloys
D. Magnetic steel alloys
Answer : B

16. Blast furnace is used to produce
A. Pig iron
B. Cast iron
C. Wrought iron
D. Steel
Answer : A

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

18. Malleable cast iron is produced
A. By adding magnesium to molten cast iron
B. By quick cooling of molten cast iron
C. From white cast iron by annealing process
D. None of these
Answer : C

19. Basic solution is one which has pH value
A. Greater than 7
B. Equal to 7
C. Less than 7
D. pH value has nothing to do with basic solution
Answer : A

20. The crystal structure of brass is
A. F.C.C.
B. B.C.C.
C. H.C.P.
D. Orthorhombic crystalline structure
Answer : A

21. The basic constituents of Hastelloy are
A. Aluminium, copper etc.
B. Nickel, molybdenum etc.
C. Nickel, Copper, etc.
D. All of the above
Answer : B

22. 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

23. Which of the following statement is incorrect about duralumin?
A. It is prone to age hardening
B. It can be forged
C. It has good machining properties
D. It is lighter than pure aluminium
Answer : D

24. Carbon steel is
A. Made by adding carbon in steel
B. Refined from cast iron
C. An alloy of iron and carbon with varying quantities of phosphorus and sulphur
D. Extensively used for making cutting tools
Answer : C

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

26. The compressive strength of cast iron is ________ that of its tensile strength.
A. Equal to
B. Less than
C. More than
D. None of these
Answer : C

27. Iron-carbon alloys containing 1.7 to 4.3% carbon are known as
A. Eutectic cast irons
B. Hypoeutectic cast irons
C. Hypereutectic cast irons
D. None of these
Answer : B

28. The coordination number of a face centred cubic space lattice is
A. Six
B. Twelve
C. Eighteen
D. Twenty
Answer : B

29. Ball bearings are, usually, made from
A. Low carbon steel
B. High carbon steel
C. Medium carbon steel
D. Chrome steel
Answer : D

30. 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

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

32. 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

33. Ductile 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 creium) in the ladle. Graphite is in nodular or spheroidal form and is well dispersed throughout the material
Answer : D

34. Brass contains
A. 70% copper and 30% zinc
B. 90% copper and 10% tin
C. 85 - 92% copper and rest tin with little lead and nickel
D. 70 - 75% copper and rest tin
Answer : A

35. 'Killed steels' are those steels
A. Which are destroyed by burning
B. Which after their destruction are recycled to produce fresh steel
C. Which are deoxidised in the ladle with silicon and aluminium
D. In which carbon is completely burnt
Answer : C

36. Which is false statement about annealing? Annealing is done to
A. Relieve stresses
B. Harden steel slightly
C. Improve machining characteristic
D. Soften material
Answer : B

37. The bond formed by transferring electrons from one atom to another is called
A. Ionic bond
B. Covalent bond
C. Metallic bond
D. None of these
Answer : A

38. The alloying element which can replace tungsten in high speed steels is
A. Nickel
B. Vanadium
C. Cobalt
D. Molybdenum
Answer : D

39. Cartridge brass can be
A. Cold rolled into sheets
B. Drawn into wires
C. Formed into tube
D. Any one of these
Answer : D

40. Preheating is essential in welding
A. Cast iron
B. High speed steel
C. All nonferrous materials
D. All of the above
Answer : A

41. The temperature at which ferromagnetic alpha iron transforms to paramagnetic alpha iron is
A. 770°C
B. 910°C
C. 1050°C
D. Below recrystallisation temperature
Answer : A

42. Babbitt metal is a
A. Lead base alloy
B. Tin base alloy
C. Copper base alloy
D. Both (A) and (C) above
Answer : D

43. A small percentage of boron is added to steel in order to
A. Increase hardenability
B. Reduce machinability
C. Increase wear resistance
D. Increase endurance strength
Answer : A

44. The property of a material which enables it to retain the deformation permanently, is called
A. Brittleness
B. Ductility
C. Malleability
D. Plasticity
Answer : D

45. In spheroidising process, the steel is
A. Heated below the lower critical temperature and then cooled slowly
B. Heated up to the lower critical temperature and then cooled in still air
C. Heated slightly above the lower critical temperature and then cooled slowly to a temperature of 600°C
D. None of the above
Answer : C

46. Stress relaxation is the phenomenon
A. In which parts are not loaded
B. In which stress remains constant on increasing load
C. In which deformation tends to loosen the joint and produces a stress reduced
D. Stress reduces on increasing load
Answer : C

47. Crystal structure of a material is, generally, examined by
A. Naked eye
B. Optical microscope
C. Metallurgical microscope
D. X-ray techniques
Answer : D

48. Bell metal contains
A. 70% copper and 30% zinc
B. 90% copper and 10% ti
C. 85 - 92% copper and rest tin with little lead and nickel
D. 70 - 75% copper and rest tin
Answer : D

49. The stiffness is the ability of a material to resist
A. Deformation under stress
B. Fracture due to high impact loads
C. Externally applied forces with breakdown or yielding
D. None of the above
Answer : A

50. Austenite is a combination of
A. Ferrite and cementite
B. Cementite and gamma iron
C. Ferrite and austenite
D. Ferrite and iron graphite
Answer : B