Engineering Materials 1000+ MCQ with answer for SSC JE

1. The usual composition of a soldering alloy is
A. Tin, lead and small percentage of antimony
B. Tin and lead
C. Tin, lead and silver
D. Tin and copper
Answer : A

2. Which one of the following metals would work-harden more quickly than the others?
A. Copper
B. Brass
C. Lead
D. Silver
Answer : B

3. In basic Bessemer process, the furnace is lined with
A. Silica bricks
B. A mixture of tar and burnt dolomite bricks
C. Both (A) and (B)
D. None of these
Answer : B

4. Sulphur in pig iron tends to make it
A. Hard
B. Soft
C. Ductile
D. Tough
Answer : A

5. German silver contains
A. 1% silver
B. 2.5% silver
C. 5% silver
D. 10% silver
Answer : C

6. Tungsten in high speed steel provides
A. Hot hardness
B. Toughness
C. Wear resistance
D. Sharp cutting edge
Answer : A

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

8. 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

9. Age-hardening is related with
A. Stainless steel
B. Gun metal
C. German silver
D. Duralumin
Answer : D

10. 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

11. In mottled cast iron, carbon is available in
A. Free form
B. Combined form
C. Nodular form
D. Partly in free and partly in combined state
Answer : D

12. The type of space lattice found in gamma-iron is
A. Face centered cubic space lattice
B. Body centered cubic space lattice
C. Close packed hexagonal space lattice
D. None of these
Answer : A

13. The carbon in the pig iron varies from
A. 0.1 to 0.5 %
B. 0.5 to 1 %
C. 1 to 5 %
D. 5 to 10 %
Answer : C

14. 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

15. Which of the following statement is true about brittle fracture?
A. High temperature and low strain rates favour brittle fracture
B. Many metals with hexagonal close packed (H.C.P) crystal structure commonly show brittle fracture
C. Brittle fracture is always preceded by noise
D. Cup and cone formation is characteristic for brittle materials
Answer : B

16. The machinability of aluminium increases when __________ is added to aluminium.
A. Copper
B. Magnesium
C. Silicon
D. Lead and bismuth
Answer : D

17. Muntz metal contains copper and zinc in the ratio of
A. 50 : 50
B. 40 : 60
C. 60 : 40
D. 20 : 80
Answer : C

18. Aluminium bronze contains aluminium and copper in the ratio of
A. 50 : 50
B. 40 : 60
C. 60 : 40
D. 10 : 90
Answer : D

19. Brass (alloy of copper and zinc) is an example of
A. Substitutional solid solution
B. Interstitial solid solution
C. Intermetallic compounds
D. All of the above
Answer : A

20. Eutectoid steel consists of
A. Wholly pearlite
B. Wholly austenite
C. Pearlite and ferrite
D. Pearlite and cementite
Answer : A

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

22. Railway rails are normally made of
A. Mild steel
B. Alloy steel
C. High carbon
D. Tungsten steel
Answer : C

23. 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

24. The aluminium alloy made by melting aluminium with 2 to 10% magnesium and 1.75% copper is called
A. Duralumin
B. Y-alloy
C. Magnalium
D. Hindalium
Answer : C

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

26. Annealing of white cast iron results in production of
A. Malleable iron
B. Nodular iron
C. Spheroidal iron
D. Grey iron
Answer : A

27. Chromium when added to steel __________ the tensile strength.
A. Does not effect
B. Decreases
C. Increases
D. None of these
Answer : C

28. When a steel containing ________ 0.8% carbon is cooled slowly below the lower critical point, it consists of ferrite and pearlite.
A. Equal to
B. Less than
C. More than
D. None of these
Answer : B

29. 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

30. Shock resistance of steel is increased by adding
A. Nickel
B. Chromium
C. Nickel and chromium
D. Sulphur, lead and phosphorus
Answer : C

31. An alloy of copper, tin and zinc is known as
A. Brass
B. Bronze
C. Gun metal
D. Muntz metal
Answer : C

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

33. Tin base white metals are used where the bearings are subjected to
A. Large surface wear
B. Elevated temperatures
C. Light load and pressure
D. High pressure and load
Answer : A

34. The correct sequence for descending order of machinability is
A. Grey cast iron, low carbon steel, wrought iron
B. Low carbon steel, grey cast iron, wrought iron
C. Wrought iron, low carbon steel, grey cast iron
D. Wrought iron, grey cast iron, low carbon steel
Answer : A

35. Addition of manganese 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 : B

36. Which of the following element results in presence of free graphite in C.I.?
A. Carbon
B. Sulphur
C. Silicon
D. Manganese
Answer : C

37. The hardness of steel increases if it contains
A. Pearlite
B. Ferrite
C. Cementite
D. Martensite
Answer : C

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

39. For the allotropic forms of iron, the points of arrest are
A. The points where no further change occurs
B. Constant for all metals
C. The points where there is no further flow of metal
D. The points of discontinuity
Answer : D

40. 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

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

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

43. An important property of malleable cast iron in comparison to grey cast iron is the high
A. Compressive strength
B. Ductility
C. Carbon content
D. Hardness
Answer : B

44. 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

45. Constantan an alloy used in thermocouples is an alloy of
A. Copper and tin
B. Copper and zinc
C. Copper and iron
D. Copper and nickel
Answer : D

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

47. 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

48. Melting point of iron is
A. 1539°C
B. 1601°C
C. 1489°C
D. 1712°C
Answer : A

49. 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

50. 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