1000+ Engineering Materials Multiple Choice Question Answer [Solved]

1. 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

2. Cast iron is characterised by minimum of following percentage of carbon
A. 0.2 %
B. 0.8 %
C. 1.3 %
D. 2 %
Answer : D

3. 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

4. Acidic solution is one which has pH value
A. Greater than 7
B. Less than 7
C. Equal to 7
D. pH value has nothing to do with neutral solution
Answer : B

5. Nodular iron has
A. High machinability
B. Low melting point
C. High tensile strength
D. All of the above
Answer : D

6. When steel containing less than 0.8% carbon is cooled slowly from temperatures above or within the critical range, it consists of
A. Mainly ferrite
B. Mainly pearlite
C. Ferrite and pearlite
D. Pearlite and cementite
Answer : C

7. 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

8. 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

9. Which of the following material has maximum ductility?
A. Mild steel
B. Copper
C. Nickel
D. Aluminium
Answer : A

10. Which of the following impurity in cast iron makes it hard and brittle?
A. Silicon
B. Sulphur
C. Manganese
D. Phosphorus
Answer : B

11. 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

12. Which of the following alloys does not contain tin?
A. White metal
B. Solder admiralty
C. Fusible metal
D. Phosphor bronze
Answer : A

13. 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

14. When medium carbon steel is heated to coarsening temperature
A. There is no change in grain size
B. The average grain size is a minimum
C. The grain size increases very rapidly
D. The grain size first increases and then decreases very rapidly
Answer : C

15. Surveying tapes are made of a material having low coefficient of expansion and enough strength. The alloy used is
A. Silver metal
B. Duralumin
C. Hastelloy
D. Invar
Answer : D

16. 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

17. Pearlite consists 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 : B

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

19. Connecting rod is, usually, made from
A. Low carbon steel
B. High carbon steel
C. Medium carbon steel
D. High speed steel
Answer : C

20. 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

21. 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

22. Tungsten in steel
A. Improves wear resistance, cutting ability and toughness
B. Refines grain size and produces less tendency to carburisation, improves corrosion and heat resistant properties
C. Improves cutting ability and reduces hardenability
D. Gives ductility, toughness, tensile strength and anticorrosion properties
Answer : B

23. The elastic stress strain behaviour of rubber is
A. Linear
B. Nonlinear
C. Plastic
D. No fixed relationship
Answer : B

24. Depth of hardness of steel is increased by addition of
A. Nickel
B. Chromium
C. Tungsten
D. Vanadium
Answer : B

25. Nodular cast iron is produced by adding ________ to the molten cast iron.
A. Nickel
B. Chromium
C. Copper
D. Magnesium
Answer : D

26. Induction hardening is basically a
A. Carburising process
B. Surface hardening process
C. Core hardening process
D. None of these
Answer : B

27. Phosphor bronze contains
A. 0.5% of phosphorous
B. 1% phosphorous
C. 2.5% phosphorous
D. None of the above
Answer : D

28. Corrosion resistance of steel is increased by addition of
A. Chromium and nickel
B. Sulphur, phosphorus, lead
C. Vanadium, aluminium
D. Tungsten, molybdenum, vanadium, chromium
Answer : A

29. Cemented carbide tools are not found to be suitable for cutting
A. Brass
B. Cast iron
C. Aluminium
D. Steel
Answer : D

30. The toughness of a material __________ when it is heated.
A. Remain same
B. Decreases
C. Increases
D. None of these
Answer : B

31. Which of the following display properties similar to that of steel?
A. Blackheart cast iron
B. White-heart cast iron
C. Both (A) and (B)
D. None of these
Answer : C

32. Gun metal 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 - 78% copper and rest tin
Answer : C

33. 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

34. Gamma iron exits at following temperature
A. Room temperature
B. Near melting point
C. Between 1400°C and 1539°C
D. Between 910°C and 1400°C
Answer : D

35. Hardness of steel depends on
A. Amount of carbon it contains
B. The shape and distribution of the carbides in iron
C. Method of fabrication
D. Contents of alloying elements
Answer : B

36. The percentage of carbon in low carbon steel is
A. 0.05 %
B. 0.15 %
C. 0.3 %
D. 0.5 %
Answer : B

37. The cupola is used to manufacture
A. Pig iron
B. Cast iron
C. Wrought iron
D. Steel
Answer : B

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

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

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

41. 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

42. 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

43. The charge is fed into the blast furnace through the
A. Stack
B. Throat
C. Bosh
D. Tyres
Answer : B

44. Delta iron occurs at temperature of
A. Room temperature
B. Above melting point
C. Between 1400°C and 1539°C
D. Between 910°C and 1400°C
Answer : C

45. The ultimate tensile strength and yield strength of most of the metals, when temperature falls from 0 to 100°C will
A. Increase
B. Decrease
C. Remain same
D. First increase and then decrease
Answer : A

46. White 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. Silver and chromium
Answer : C

47. The alloying element which reduces the formation of iron sulphide in steel is
A. Chromium
B. Nickel
C. Vanadium
D. Manganese
Answer : D

48. Mild steel belongs to the following category
A. Low carbon steel
B. Medium carbon steel
C. High carbon steel
D. Alloy steel
Answer : A

49. Nickel in steel
A. Improves wear resistance, cutting ability and toughness
B. Refines grain size and produces less tendency to carburisation, improves corrosion and heat resistant properties
C. Improves cutting ability and reduces hardenability
D. Gives ductility, toughness, tensile strength and anticorrosion properties
Answer : D

50. Sulphur in cast iron
A. Makes the iron soft and easily machinable
B. Increases hardness and brittleness
C. Make the iron white and hard
D. Aids fusibility and fluidity
Answer : B