Engineering Materials 1000+ MCQ with answer for SSC CHSL

1. Corrosion resistance of steel is increased by adding
A. Chromium and nickel
B. Nickel and molybdenum
C. Aluminium and zinc
D. Tungsten and sulphur
Answer : A

2. Bronze is an alloy of
A. Copper and zinc
B. Copper and tin
C. Copper, tin and zinc
D. None of these
Answer : B

3. The hardness of steel primarily depends on
A. Percentage of carbon
B. Percentage of alloying elements
C. Heat treatment employed
D. Shape of carbides and their distribution in iron
Answer : D

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

5. Which of the following elements does not impart hardness to steel?
A. Copper
B. Chromium
C. Nickel
D. Silicon
Answer : A

6. There are fourteen atoms in a unit cell of
A. Body centred cubic space lattice
B. Face centred cubic space lattice
C. Close packed hexagonal space lattice
D. None of these
Answer : B

7. The composition of silver solder is
A. Silver, copper, zinc
B. Silver, tin, nickel
C. Silver, lead, zinc
D. Silver, copper, aluminium
Answer : A

8. The correct composition of Babbitt metal is
A. 87.75% Sn, 4% Cu, 8% Sb, 0.25% Bi
B. 90% Sn, 2% Cu, 4% Sb, 2% Bi, 2% Mg
C. 87% Sn, 4% Cu, 8% Sb, 1% Al
D. 82% Sn, 4% Cu, 8% Sb, 3% Al, 3% Mg
Answer : A

9. Cementite consist of
A. 13% carbon and 87% ferrite
B. 13% cementite and 87% ferrite
C. 13% ferrite and 87% cementite
D. 6.67% carbon and 93.33% iron
Answer : D

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

11. 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

12. The main alloying elements high speed steel in order of increasing proportion are
A. Vanadium, chromium, tungsten
B. Tungsten, titanium, vanadium
C. Chromium, titanium, vanadium
D. Tungsten, chromium, titanium
Answer : A

13. 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

14. The coke in the charge of blast furnace
A. Controls the grade of pig iron
B. Acts as an iron bearing mineral
C. Supplies heat to reduce ore and melt the iron
D. Forms a slag by combining with impurities
Answer : C

15. The percentage of carbon in pig iron varies from
A. 0.1 to 1.2%
B. 1.5 to 2.5%
C. 2.5 to 4%
D. 4 to 4.5%
Answer : D

16. Pure iron is the structure of
A. Ferrite
B. Pearlite
C. Austenite
D. Ferrite and cementite
Answer : A

17. Babbitt metal is a
A. Lead base alloy
B. Copper base alloy
C. Tin base alloy
D. Cadmium base alloy
Answer : C

18. The hardness is the property of a material due to which it
A. Can be drawn into wires
B. Breaks with little permanent distortion
C. Can cut another metal
D. Can be rolled or hammered into thin sheets
Answer : C

19. Closed packed hexagonal space lattice is found in
A. Zinc, magnesium, cobalt, cadmium, antimony and bismuth
B. Gamma-iron, aluminium, copper, lead, silver and nickel
C. Alpha-iron, tungsten, chromium and molybdenum
D. None of the above
Answer : A

20. The brown smoke during the operation of a Bessemer converter indicates that the
A. Air is burning out silicon and manganese
B. Silicon and manganese has burnt and carbon has started oxidising
C. The converter must be titled to remove the contents of the converter
D. The brown smoke does not occur during the operation of a Bessemer converter
Answer : A

21. Which of the following pipes is least corrosion resistant?
A. Brass
B. Mild steel
C. Cast iron
D. Wrought iron
Answer : D

22. Which of the following has a fine gold colour and is used for imitation jewellery?
A. Silicon bronze
B. Aluminium bronze
C. Gun metal
D. Babbitt metal
Answer : B

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

24. Which is the false statement about wrought iron? It has
A. High resistance to rusting and corrosion
B. High ductility
C. Ability of hold protective coating
D. Uniform strength in all directions
Answer : D

25. Basic constituents of Monel metal are
A. Nickel, copper
B. Nickel, molybdenum
C. Zinc, tin, lead
D. Nickel, lead and tin
Answer : A

26. 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

27. When the steel is normalised, its
A. Yield point increases
B. Ductility decreases
C. Ultimate tensile strength increases
D. All of these
Answer : D

28. The machinability of steel is increased by
A. Silicon and sulphur
B. Phosphorous, lead and sulphur
C. Sulphur, graphite and aluminium
D. Phosphorous and aluminium
Answer : B

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

30. The loss of strength in compression with simultaneous gain in strength in tension due to overloading is known as
A. Hysteresis
B. Creep
C. Visco elasticity
D. Boeschinger effect
Answer : D

31. The addition of which of the following improves machining of copper?
A. Sulphur
B. Vanadium
C. Tin
D. Zinc
Answer : A

32. The hardness and tensile strength in austenitic stainless steel can be increased by
A. Hardening and cold working
B. Normalising
C. Martempering
D. Full annealing
Answer : A

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

34. 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

35. Which of the following statements are true for annealing of steels?
A. Steels are heated to 500 to 700°C
B. Cooling is done slowly and steadily
C. Internal stresses are relieved
D. All of these
Answer : D

36. The material in which the atoms are arranged regularly in some directions but not in others, is called
A. Amorphous material
B. Mesomorphous material
C. Crystalline material
D. None of these
Answer : B

37. Silicon when added to copper improves
A. Machinability
B. Hardness
C. Hardness and strength
D. Strength and ductility
Answer : C

38. Thermoplastic materials are those materials which
A. Are formed into shape under heat and pressure and results in a permanently hard product
B. Do not become hard with the application of heat and pressure and no chemical change occurs
C. Are flexible and can withstand considerable wear under suitable conditions
D. Are used as a friction lining for clutches and brakes
Answer : B

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

40. Which of the following is the binding material in cemented carbides?
A. Cobalt
B. Nickel
C. Vanadium
D. Iron
Answer : A

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

42. Cyaniding is the process of
A. Dipping steel in cyanide bath
B. Reacting steel surface with cyanide salts
C. Adding carbon and nitrogen by heat treatment of steel to increase its surface hardness
D. Obtaining cyanide salts
Answer : C

43. Lead is poured into the joint between two pipes. These pipes may be made of
A. Cast iron
B. Vitrified clay
C. Asbestos cement
D. Concrete
Answer : A

44. Recrystallisation temperature can be lowered by
A. Purification of metal
B. Grain refinement
C. Working at lower temperature
D. All of the above
Answer : D

45. 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

46. 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

47. 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

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

49. Which of the following impurity in cast iron promotes graphite nodule formation and increases the fluidity of the molten metal?
A. Silicon
B. Sulphur
C. Manganese
D. Phosphorus
Answer : A

50. When filing or machining cast iron makes our hands black, then it shows that ________ is present in cast iron.
A. Cementite
B. Free graphite
C. Both A and B
D. None of these
Answer : B