Material Science 4

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Mechanical Engineering MCQ Question Papers: DRDO, ISRO, Interview

Subject:  Material Science 4

Part 4: List for questions and answers of Material Science

Q1. Silicon when added to copper improves
a) Machinability
b) Hardness
c) Hardness and strength
d) Strength and ductility

Q2. The alloying element which increases residual magnetism and coercive magnetic force in steel for magnets is
a) Chromium
b) Nickel
c) Vanadium
d) Cobalt

Q3. Cast iron is manufactured in
a) Blast furnace
b) Cupola
c) Open hearth furnace
d) Bessemer converter

Q4. The lower critical point for all steels is
a) 600°C
b) 700°C
c) 723°C
d) 913°C

Q5. Haematite iron ore contains iron about
a) 30%
b) 45%
c) 55%
d) 70%

Q6. 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

Q7. Crystal structure of a material is, generally, examined by
a) Naked eye
b) Optical microscope
c) Metallurgical microscope
d) X-ray techniques

Q8. Iron-carbon alloys containing 1.7 to 4.3% carbon are known as
a) Eutectic cast irons
b) Hypo-eutectic cast irons
c) Hyper-eutectic cast irons
d) None of these

Q9. 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

Q10. The heat treatment process used for softening hardened steel is
a) Carburising
b) Normalising
c) Annealing
d) Tempering

Q11. The electric process of steel making is especially adopted to
a) Alloy and carbon tool steel
b) Magnet steel
c) High speed tool steel
d) All of these

Q12. The hardness of steel increases if it contains
a) Pearlite
b) Ferrite
c) Cementite
d) Martensite

Q13. 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

Q14. 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

Q15. Nodular cast iron is produced by adding __________ to the molten cast iron
a) Nickel
b) Cnhromium
c) Copper
d) Magnesium

Q16. The cupola is used to manufacture
a) Pig iron
b) Cast iron
c) Wrought iron
d) Steel

Q17. The type of space lattice found in gamma-iron is
a) Face centred cubic space lattice
b) Body centred cubic space lattice
c) Close packed hexagonal space lattice
d) None of these

Q18. The property of a material due to which it breaks with little permanent distortion, is
called
a) Brittleness
b) Ductility
c) Malleability
d) Plasticity

Q19. 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

Q20. Free carbon in iron makes the metal
a) Soft and gives a coarse grained crystalline structure
b) Soft and gives a fine grained crystalline structure
c) Hard and gives a coarse grained crystalline structure
d) Hard and gives a fine grained crystalline structure

Part 4: List for questions and answers of Material Science

Q1. Answer: c

Q2. Answer: d

Q3. Answer: b

Q4. Answer: c

Q5. Answer: d

Q6. Answer: b

Q7. Answer: d

Q8. Answer: b

Q9. Answer: c

Q10. Answer: d

Q11. Answer: d

Q12. Answer: c

Q13. Answer: b

Q14. Answer: c

Q15. Answer: d

Q16. Answer: b

Q17. Answer: a

Q18. Answer: a

Q19. Answer: a

Q20. Answer: a