1000+ Engineering Materials Multiple Choice Question Answer [Solved]

1. The ability of a material to resist softening at high temperature is known as
A. Creep
B. Hot tempering
C. Hot hardness
D. Fatigue
Answer : C

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

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

4. In compression, a prism of brittle material will break
A. By forming a bulge
B. By shearing along oblique plane
C. In direction perpendicular to application of load
D. By crushing into thousands of pieces
Answer : B

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

6. The machinability of steel is improved by adding
A. Nickel
B. Chromium
C. Nickel and chromium
D. Sulphur, lead and phosphorus
Answer : D

7. According to Indian standard specifications, plain carbon steel designated by 40 C8 means that the carbon content is
A. 0.04 %
B. 0.35 to 0.45 %
C. 0.4 to 0.6 %
D. 0.6 to 0.8 %
Answer : B

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

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

10. In the lower part of the blast furnace (zone of fusion), the temperature is
A. 400° to 700°C
B. 800°C to 1000°C
C. 1200°C to 1300°C
D. 1500°C to 1700°C
Answer : C

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

12. 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

13. 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

14. 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

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

16. Manganese in steel increases its
A. Tensile strength
B. Hardness
C. Ductility
D. Fluidity
Answer : A

17. 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

18. Eutectoid reaction occurs at
A. 600°C
B. 723°C
C. 1147°C
D. 1493°C
Answer : B

19. 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

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

21. White 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 : B

22. Admiralty brass used for steam condenser tubes contains copper and zinc in the following ratio
A. 50 : 50
B. 30 : 70
C. 70 : 30
D. 40 : 60
Answer : B

23. 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

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

25. 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

26. 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

27. 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

28. The following types of materials are usually the most ductile
A. Face centred cubic lattice
B. Body centred cubic lattice
C. Hexagonal close packed lattice
D. All of the above
Answer : A

29. 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

30. Dislocations in materials refer to the following type of defect
A. Point defect
B. Line defect
C. Plane defect
D. Volumetric defect
Answer : B

31. Beryllium bronze contains
A. 60% copper and 40% beryllium
B. 80% copper and 20% beryllium
C. 97.75% copper and 2.25% beryllium
D. 99% copper and 1% beryllium
Answer : C

32. 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

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

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

35. White cast iron contains carbon in the form of
A. Free carbon
B. Graphite
C. Cementite
D. White carbon
Answer : C

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

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

38. An example of amorphous material is
A. Zinc
B. Lead
C. Silver
D. Glass
Answer : D

39. 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

40. In low carbon steels, ________ raises the yield point and improves the resistance to atmospheric corrosion.
A. Sulphur
B. Phosphorus
C. Manganese
D. Silicon
Answer : B

41. 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

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

43. Which is false statement about case hardening? Case hardening is done by
A. Electroplating
B. Cyaniding
C. Induction hardening
D. Nitriding
Answer : A

44. Iron-carbon alloys containing carbon ________ 4.3% are known as hypereutectic cast irons.
A. Equal to
B. Less than
C. More than
D. None of these
Answer : C

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

46. Which of the following metal shrinks most from molten state to solid state?
A. Cast iron
B. Cast steel
C. Brass
D. Admiralty metal
Answer : D

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

48. In process annealing, 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 : D

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

50. 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