Engineering Materials Multiple choice Questions
1. The composition of silver solder is
A. Silver, copper, zinc
B. Silver, tin, nickel
C. Silver, lead, zinc
D. Silver, copper, aluminium
Answer: A
2. 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
3. Pipes for bicycle frames are made of
A. Cold rolled steel
B. Hot rolled steel
C. Forged steel
D. Cast steel
Answer: A
4. Which one of the following metals would work-harden more quickly than the others?
A. Copper
B. Brass
C. Lead
D. Silver
Answer: B
5. Iron-carbon alloys containing carbon ________ 4.3% are known as hyper-eutectic cast irons.
A. Equal to
B. Less than
C. More than
D. None of these
Answer: C
6. Bell 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 – 75% copper and rest tin
Answer: D
7. The temperature required for full annealing in hypereutectoid steel is
A. 30° C to 50° C above upper critical temperature
B. 30° C to 50° C below upper critical temperature
C. 30° C to 50° C above lower critical temperature
D. 30° C to 50° C below lower critical temperature
Answer: C
8. The charge of the blast furnace consists of
A. Calcined ore (8 parts), coke (4 parts) and limestone (1 part)
B. Calcined ore (4 parts), coke (1 part) and limestone (8 parts)
C. Calcined ore (1 part), coke (8 parts) and limestone (4 parts)
D. Calcined ore, coke and limestone all in equal parts
Answer: A
9. The following element can’t impart high strength at elevated temperature
A. Manganese
B. Magnesium
C. Nickel
D. Silicon
Answer: B
10. The percentage carbon content in wrought iron is about
A. 0.02
B. 0.1
C. 02
D. 0.4
Answer: A
11. Heavy duty leaf and coil springs contain carbon of the following order
A. 0.2%
B. 0.5%
C. 0.8%
D. 1.0%
Answer: D
12. The silicon steel is widely used for
A. Connecting rods
B. Cutting tools
C. Generators and transformers in the form of laminated cores
D. Motor car crankshafts
Answer: C
13. Blast furnace produces following by reduction of iron ore
A. Cast iron
B. Pig iron
C. Wrought iron
D. Malleable iron
Answer: B
14. For a steel containing 0.8% carbon
A. There is no critical point
B. There is only one critical point
C. There are two critical points
D. There can be any number of critical points
Answer: B
15. 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 anti-corrosion properties
Answer: D
16. Which of the following impurity in cast iron makes it hard and brittle?
A. Silicon
B. Sulphur
C. Manganese
D. Phosphorus
(1) Answer: B
17. Tensile strength of steel can be safely increased by
A. Adding carbon up to 2.8%
B. Adding carbon up to 6.3%
C. Adding carbon up to 0.83%
D. Adding small quantities of copper
Answer: C
18. Which of the following metal is used for nuclear energy?
A. Uranium
B. Thorium
C. Niobium
D. All of these
Answer: D
19. Cemented carbide tools are not found to be suitable for cutting
A. Brass
B. Cast iron
C. Aluminium
D. Steel
Answer: D
20. Y-alloy contains
A. 3.5 to 4.5% copper, 0.4 to 0.7% magnesium, 0.4 to 0.7% manganese and rest aluminium
B. 3.5 to 4.5% copper, 1.2 to 1.7% manganese, 1.8 to 2.3% nickel, 0.6% each of silicon, magnesium and iron, and rest aluminium
C. 4 to 4.5% magnesium, 3 to 4% copper and rest aluminium
D. 5 to 6% tin, 2 to 3% copper and rest aluminium
Answer: B
21. Amorphous material is one
A. In which atoms align themselves in a geometric pattern upon solidification
B. In which there is no definite atomic structure and atoms exist in a random pattern just as in a liquid
C. Which is not attacked by phosphorous
D. Which emits fumes on melting
Answer: B
22. According to Indian standard specifications, SG 400/15 means
A. Spheroidal graphite cast iron with B.H.N. 400 and minimum tensile strength 15 MPa
B. Spheroidal graphite cast iron with minimum tensile strength 400 MPa and 15 percent elongation
C. Spheroidal graphite cast iron with minimum compressive strength 400 MPa and 15 percent reduction in area
D. None of the above
Answer: B
23. 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
24. 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
25. Pick up the wrong statement
A. Aluminium in steel results in excessive grain growth
B. Manganese in steel induces hardness
C. Nickel and chromium in steel helps in raising the elastic limit and improve the resilience and ductility
D. Tungsten in steels improves magnetic properties and hardenability
Answer: A
26. A coarse grained steel
A. Is less tough and has a greater tendency to distort during heat treatment
B. Is more ductile and has a less tendency to distort during heat treatment
C. Is less tough and has a less tendency to distort during heat treatment
D. Is more ductile and has a greater tendency to distort during heat treatment
Answer: A
27. Pick up the wrong statement Nickel and chromium in steel help in
A. Providing corrosion resistance
B. Improving machining properties
C. Providing high strength at elevated temperatures
D. Raising the elastic limit
Answer: B
28. Normalising of steel is done to
A. Refine the grain structure
B. Remove strains caused by cold working
C. Remove dislocations caused in the internal structure due to hot working
D. All of the above
Answer: D
29. Steel contains
A. 80% or more iron
B. 50% or more iron
C. Alloying elements like chromium, tungsten nickel and copper
D. Elements like phosphorus, sulphur and silicon in varying quantities
Answer: B
30. 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
31. 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
32. Which of the following statement is wrong?
A. Steel with 0.8% carbon is wholly pearlite
B. The amount of cementite increases with the increase in percentage of carbon in iron
C. A mechanical mixture of 87% cementite and 13% ferrite is called pearlite
D. The cementite is identified as round particles in the structure
Answer: C
33. 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
34. 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
35. 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
36. 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
37. Dow metal contains
A. 94% aluminium, 4% copper and 0.5% Mn, Mg, Si and Fe
B. 92.5% aluminium and, 4% copper, 2% nickel and 1.5% Mg
C. 90% aluminium and 90% copper
D. 90% magnesium and 9% aluminium with some copper
Answer: D
38. Body centered cubic 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: C
39. Which of the following alloys does not have copper as one of the constituents?
A. Delta metal
B. Monel metal
C. Constantan
D. Nichrome
Answer: D
40. In spheroidising process, the steel is
A. Heated below the lower critical temperature and then cooled slowly
B. Heated up to the lower critical temperature and then cooled in still air
C. Heated slightly above the lower critical temperature and then cooled slowly to a temperature of 600°C
D. None of the above
Answer: C
41. Which of the following alloys does not contain tin?
A. White metal
B. Solder admiralty
C. Fusible metal
D. Phosphor bronze
Answer: A
42. The bond formed by transferring electrons from one atom to another is called
A. Ionic bond
B. Covalent bond
C. Metallic bond
D. None of these
Answer: A
43. 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
44. 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
45. Admiralty gun metal contains
A. 63 to 67% nickel and 30% copper
B. 88% copper, 10% tin and rest zinc
C. Alloy of tin, lead and cadmium
D. Iron scrap and zinc
Answer: B
46. The alloy, mainly used for corrosion resistance in stainless steels is
A. Silicon
B. Manganese
C. Carbon
D. Chromium
Answer: D
47. 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
48. Duralumin contains
A. 3.5 to 4.5% copper, 0.4 to 0.7% magnesium, 0.4 to 0.7% manganese and rest aluminium
B. 3.5 to 4.5% copper, 1.2 to 1.7% manganese, 1.8 to 2.3% nickel, 0.6% each of silicon, magnesium and iron, and rest aluminium
C. 4 to 4.5% magnesium, 3 to 4% copper and rest aluminium
D. 5 to 6% tin, 2 to 3% copper and rest aluminium
Answer: A
49. 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
50. A steel containing 16 to 18% chromium and about 0.12% carbon is called
A. Ferritic stainless steel
B. Austenitic stainless steel
C. Martenistic stainless steel
D. Nickel steel
Answer: A
51. Ductile 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: D
52. Which of the following iron exist between 910°C and 1403°C?
A. α-iron
B. β-iron
C. γ-iron
D. δ-iron
Answer: C
53. 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
54. The presence of hydrogen in steel causes
A. Reduced neutron absorption cross-section
B. Improved Weldability
C. Embrittlement
D. Corrosion resistance
Answer: C
55. 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
56. Which of the following is added in low carbon steels to prevent them from becoming porous?
A. Sulphur
B. Phosphorus
C. Manganese
D. Silicon
Answer: D
57. Which of the following element results in presence of free graphite in C.I.?
A. Carbon
B. Sulphur
C. Silicon
D. Manganese
Answer: C
58. Free cutting steels
A. Contain carbon in free from
B. Require minimum cutting force
C. Is used where rapid machining is the prime requirement
D. Can be cut freely
Answer: C
59. 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
60. The aluminium alloy, mainly used, for anodized utensil manufacture, is
A. Duralumin
B. Y-alloy
C. Magnalium
D. Hindalium
Answer: D
61. 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
62. 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
63. Monel 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. Malleable iron and zinc
Answer: A
64. 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
65. The temperature at which ferromagnetic alpha iron transforms to paramagnetic alpha iron is
A. 770°C
B. 910°C
C. 1050°C
D. Below recrystallization temperature
Answer: A
66. 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
67. Which is false statement about annealing? Annealing is done to
A. Relieve stresses
B. Harden steel slightly
C. Improve machining characteristic
D. Soften material
Answer: B
68. When low carbon steel is heated up to upper critical 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: B
69. Dislocations in materials refer to the following type of defect
A. Point defect
B. Line defect
C. Plane defect
D. Volumetric defect
Answer: B
70. 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
71. Sulphur in steel
A. Acts as deoxidiser
B. Reduces the grain size
C. Decreases tensile strength and hardness
D. Lowers the toughness and transverse ductility
Answer: D
72. The toughness of a material __________ when it is heated.
A. Remain same
B. Decreases
C. Increases
D. None of these
Answer: B
73. Structural steel contains following principal alloying elements
A. Nickel, chromium and manganese
B. Tungsten, molybdenum and phosphorous
C. Lead, tin, aluminium
D. Zinc, sulphur, and chromium
Answer: A
74. In basic Bessemer process, the furnace is lined with
A. Silica bricks
B. A mixture of tar and burnt dolomite bricks
C. BothA. andB.
D. None of these
Answer: B
75. 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
76. The material in which the atoms are arranged chaotically, is called
A. Amorphous material
B. Mesomorphous material
C. Crystalline material
D. None of these
Answer: A
77. 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
78. Crystal structure of a material is, generally, examined by
A. Naked eye
B. Optical microscope
C. Metallurgical microscope
D. X-ray techniques
Answer: D
79. 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
80. An eutectoid steel consists of
A. Wholly pearlite
B. Wholly austenite
C. Pearlite and ferrite
D. Pearlite and cementite
Answer: A
81. Ductility of a material can be defined as
A. Ability to undergo large permanent deformations in compression
B. Ability to recover its original form
C. Ability to undergo large permanent deformations in tension
D. All of the above
Answer: C
82. Which of the following property is desirable in parts subjected to shock and impact loads?
A. Strength
B. Stiffness
C. Brittleness
D. Toughness
Answer: D
83. 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
84. 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
85. Corundum contains more than 95%
A. Steel
B. Al2O3
C. SiO2
D. MgO
Answer: B
86. 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
87. Brass 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 – 75% copper and rest tin
Answer: A
88. There are fourteen atoms in a unit cell of
A. Body centered cubic space lattice
B. Face centered cubic space lattice
C. Close packed hexagonal space lattice
D. None of these
Answer: B
89. A specimen of aluminium metal when observed under microscope shows
A. B.C.C. crystalline structure
B. F.C.C. crystal structure
C. H.C.P. structure
D. A complex cubic structure
Answer: B
90. The defect which takes place due to imperfect packing of atoms during crystallization is known as
A. Line defect
B. Surface defect
C. Point defect
D. None of these
Answer: C
91. 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
92. 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
93. 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
94. Gamma-iron occurs between the temperature ranges of
A. 400°C to 600°C
B. 600°C to 900°C
C. 900°C to 1400°C
D. 1400°C to 1530°C
Answer: C
95. Alnico, an alloy used extensively for permanent magnets contains iron, nickel, aluminium and cobalt in the following ratio
A. 50 : 20 : 20 : 10
B. 40 : 30 : 20 : 10
C. 50 : 20 : 10 : 20
D. 30 : 20 : 30 : 20
Answer: A
96. 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
97. If a refractory contains high content of silicon, it means refractory is
A. Acidic
B. Basic
C. Neutral
D. Brittle
Answer: C
98. 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
99. 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
100. 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
101. 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
102. The metal suitable for bearings subjected to heavy loads, is
A. Silicon bronze
B. White metal
C. Monel metal
D. Phosphor bronze
Answer: B
103. Which of the following elements does not impart hardness to steel?
A. Copper
B. Chromium
C. Nickel
D. Silicon
Answer: A
104. In low carbon steels, presence of small quantities of sulphur improves
A. Weldability
B. Formability
C. Machinability
D. Hardenability
Answer: C
105. 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
106. 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
107. 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 anti-corrosion properties
Answer: B
108. The ability of a material to resist fracture due to high impact loads, is called
A. Strength
B. Stiffness
C. Toughness
D. Brittleness
Answer: C
109. Which is false statement about normalizing? Normalizing is done to
A. Refine grain structure
B. Reduce segregation in casting
C. Improve mechanical properties
D. Induce stresses
Answer: D
110. Hematite iron ore contains iron about
A. 30%
B. 45%
C. 55%
D. 70%
Answer: D
111. The surface hardness of the following order is achieved by nitriding operation
A. 600 VPN
B. 1500 VPN
C. 1000 to 1100 VPN
D. 250 VPN
Answer: C
112. The unit cells
A. Contain the smallest number of atoms which when taken together have all the properties of the crystals of the particular metal
B. Have the same orientation and their similar faces are parallel
C. May be defined as the smallest parallelepiped which could be transposed in three coordinate directions to build up the space lattice
D. All of the above
Answer: D
113. Which of the following represents the allotropic forms of iron?
A. Alpha iron, beta iron and gamma iron
B. Alpha iron and beta iron
C. Body centered cubic iron and face centered cubic iron
D. Alpha iron, gamma from and delta iron
Answer: D
114. Which of the following property is desirable for materials used in tools and machines?
A. Elasticity
B. Plasticity
C. Ductility
D. Malleability
Answer: A
115. Points of arrest for iron correspond to
A. Stages at which allotropic forms change
B. Stages at which further heating does not increase temperature for some time
C. Stages at which properties do not change with increase in temperature
D. There is nothing like points of arrest
Answer: A
116. The portion of the blast furnace below its widest cross-section is called
A. Hearth
B. Stack
C. Bosh
D. Throat
Answer: C
117. Taps dies and drills contain carbon
A. Below 0.5%
B. Below 1%
C. Above 1%
D. Above 2.2%
Answer: C
118. 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
119. The percentage of carbon in grey iron castings usually varies between
A. 0.5 to 1%
B. 1.2%
C. 2.5 to 4.5%
D. 5 to 7%
Answer: C
120. The machinability of steel is improved by adding
A. Nickel
B. Chromium
C. Nickel and chromium
D. Sulphur, lead and phosphorus
Answer: D
121. 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
122. Macrostructure of a material is, generally, examined by
A. Naked eye
B. Optical microscope
C. Metallurgical microscope
D. X-ray techniques
Answer: A
123. Which of the following pipes is least corrosion resistant?
A. Brass
B. Mild steel
C. Cast iron
D. Wrought iron
Answer: D
124. Wrought iron
A. Is a ductile material
B. Can be easily forged or welded
C. Cannot stand sudden and excessive shocks
D. All of these
Answer: D
125. The metallic structure of mild steel is
A. Body centered cubic
B. Face centered cubic
C. Hexagonal close packed
D. Cubic structure
Answer: A
126. 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
127. Vanadium in high speed steels
A. Promotes decarburisation
B. Provides high hot hardness
C. Forms very hard carbides and thus increases wear resistance
D. Promotes retention of austenite
Answer: C
128. Which of the following material has nearly zero coefficient of expansion?
A. Stainless steel
B. High speed steel
C. Invar
D. Heat resisting steel
Answer: C
129. Nodular iron has
A. High machinability
B. Low melting point
C. High tensile strength
D. All of the above
Answer: D
130. The addition of which of the following improves machining of copper?
A. Sulphur
B. Vanadium
C. Tin
D. Zinc
Answer: A
131. Pig iron is the name given to
A. Raw material for blast furnace
B. Product of blast furnace made by reduction of iron ore
C. Iron containing huge quantities of carbon
D. Iron in molten form in the ladles
Answer: B
132. 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
133. 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
134. Which of the following statement is correct?
A. The product produced by blast-furnace is called cast iron
B. The pig iron is the name given to the product produced by cupola
C. The cast iron has high tensile strength
D. The chilled cast iron has no graphite
Answer: D
135. Muntz metal contains copper and zinc in the ratio of
A. 50 : 50
B. 40 : 60
C. 60 : 40
D. 20 : 80
Answer: C
136. 1841 high speed steel contains
A. Vanadium 4%, chromium 18% and tungsten 1%
B. Vanadium 1%, chromium 4% and tungsten 18%
C. Vanadium 18%, chromium 1% and tungsten 4%
D. None of the above
Answer: B
137. Age-hardening is related with
A. Stainless steel
B. Gun metal
C. German silver
D. Duralumin
Answer: D
138. 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
139. Recrystallization temperature can be lowered by
A. Purification of metal
B. Grain refinement
C. Working at lower temperature
D. All of the above
Answer: D
140. The ability of a material to absorb energy in the plastic range is called
A. Resilience
B. Creep
C. Fatigue strength
D. Toughness
Answer: A
141. Maximum percentage of carbon in austenite is
A. 0.025%
B. 0.26%
C. 0.8%
D. 1.7%
Answer: D
142. 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
143. Super conduction by metals is observed in the temperature range of
A. Below 10°K
B. Above 100°K
C. Around 0°C
D. Around 100°C
Answer: A
144. Connecting rod is, usually, made from
A. Low carbon steel
B. High carbon steel
C. Medium carbon steel
D. High speed steel
Answer: C
145. Ferromagnetic alpha iron exists in temperature range of
A. Below 723°C
B. 770 to 910°C
C. 910 to 1440°C
D. 1400 to 1539°C
Answer: A
146. 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
147. 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
148. Inconel contains
A. 65% nickel, 15% chromium and 20% iron
B. 68% nickel, 29% copper and 3% other constituents
C. 80% nickel and 20% chromium
D. 80% nickel, 14% chromium and 6% iron
Answer: D
149. A reversible change in the atomic structure of the steel with a corresponding change in the properties is known as
A. Allotropic change
B. Recrystallization
C. Heat treatment
D. Precipitation
Answer: A
150. A material is said to be allotropic, if it has
A. Fixed structure at all temperatures
B. Atoms distributed in random pattern
C. Different crystal structures at different temperatures
D. Any one of the above
Answer: C
Engineering Materials objective questions with answers pdf download online exam test
151. An important property of high silicon (12-18%) cast iron is the high
A. Hardness
B. Brittleness
C. Plasticity
D. Ductility
Answer: A
152. Dye penetrant method is generally used to locate
A. Core defects
B. Surface defects
C. Superficial defects
D. Temporary defects
Answer: B
153. 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
154. Delta-iron occurs between the temperature ranges of
A. 400°C to 600°C
B. 600°C to 900°C
C. 900°C to 1400°C
D. 1400°C to 1530°C
Answer: D
155. White cast iron contains carbon in the form of
A. Free carbon
B. Graphite
C. Cementite
D. White carbon
Answer: C
156. The heat treatment process used for softening hardened steel is
A. Carburising
B. Normalizing
C. Annealing
D. Tempering
Answer: D
157. Stress relaxation is the phenomenon
A. In which parts are not loaded
B. In which stress remains constant on increasing load
C. In which deformation tends to loosen the joint and produces a stress reduced
D. Stress reduces on increasing load
Answer: C
158. Babbitt metal is a
A. Lead base alloy
B. Copper base alloy
C. Tin base alloy
D. Cadmium base alloy
Answer: C
159. Hardness of lower bainite (tempered martensite) is about
A. RC 65
B. RC 48
C. RC 57
D. RC 80
Answer: C
160. Silicon when added to copper improves
A. Machinability
B. Hardness
C. Hardness and strength
D. Strength and ductility
Answer: C
161. 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
162. 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 oxidizing
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
163. The percentage of carbon in low carbon steel is
A. 0.05%
B. 0.15%
C. 0.3%
D. 0.5%
Answer: B
164. 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
Answer: A
165. Neutral 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: C
166. The coordination number of a face centered cubic space lattice is
A. Six
B. Twelve
C. Eighteen
D. Twenty
Answer: B
167. 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
168. Brass is an alloy of
A. Copper and zinc
B. Copper and tin
C. Copper, tin and zinc
D. None of these
Answer: A
169. Malleability of a material can be defined as
A. Ability to undergo large permanent deformations in compression
B. Ability to recover its original form
C. Ability to undergo large permanent deformations in tension
D. All of the above
Answer: A
170. 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
171. Which of the following is not the correct method of increasing fatigue limit?
A. Shot peening
B. Nitriding of surface
C. Cold working
D. Surface decarburisation
Answer: D
172. 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
Answer: B
173. Materials after cold working are subjected to following process to relieve stresses
A. Hot working
B. Tempering
C. Normalizing
D. Annealing
Answer: D
174. Iron-carbon alloys containing 1.7 to 4.3% carbon are known as
A. Eutectic cast irons
B. Hypoeutectic cast irons
C. Hypereutectic cast irons
D. None of these
Answer: B
175. Which is false statement about case hardening? Case hardening is done by
A. Electroplating
B. Cyaniding
C. Induction hardening
D. Nitriding
Answer: A
176. White cast iron has
A. Carbon in the form of carbide
B. Low tensile strength
C. High compressive strength
D. All of these
Answer: D
177. Following elements have face-centered 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
178. When low carbon steel is heated up to lower critical 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: A
179. The molecules in a solid move
A. In a random manner
B. In a haphazard way
C. In circular motion
D. Back and forth like tiny pendulums
Answer: D
180. Balls for ball bearings are made of
A. Cast iron
B. Mild steel
C. Stainless steel
D. Carbon-chrome steel
Answer: D
181. Which of the following display properties similar to that of steel?
A. Blackheart cast iron
B. Whiteheart cast iron
C. BothA. andB.
D. None of these
Answer: C
182. Which is false statement about properties of aluminium?
A. Modulus of elasticity is fairly low
B. Wear resistance is very good
C. Fatigue strength is not high
D. Creep strength limits its use to fairly low temperatures
Answer: B
183. The steel widely used for motor car crankshafts is
A. Nickel steel
B. Chrome steel
C. Nickel-chrome steel
D. Silicon steel
Answer: B
184. Foundry crucible is made of
A. Mild steel
B. German silver
C. Lead
D. Graphite
Answer: D
185. The stiffness is the ability of a material to resist
A. Deformation under stress
B. Fracture due to high impact loads
C. Externally applied forces with breakdown or yielding
D. None of the above
Answer: A
186. 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
187. The type of space lattice found in alpha-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: B
188. Mild steel belongs to the following category
A. Low carbon steel
B. Medium carbon steel
C. High carbon steel
D. Alloy steel
Answer: A
189. 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
190. The ultimate tensile strength of low carbon steel by working at a high strain rate will
A. Decrease
B. Increase
C. Remain constant
D. First increase and then decrease
Answer: B
191. When elements like nickel, chromium, copper and molybdenum are added to the molten cast iron, it produces
A. White cast iron
B. Nodular cast iron
C. Malleable cast iron
D. Alloy cast iron
Answer: D
192. Slow plastic deformation of metals under a constant stress is known as
A. Creep
B. Fatigue
C. Endurance
D. Plastic deformation
Answer: A
193. The elastic stress strain behavior of rubber is
A. Linear
B. Nonlinear
C. Plastic
D. No fixed relationship
Answer: B
194. 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
195. Which of the following metal is used in making electrical resistance wire for electric furnaces and heating elements?
A. Babbitt metal
B. Monel metal
C. Nichrome
D. Phosphor bronze
Answer: C
196. Recrystallization temperature is one
A. At which crystals first start forming from molten metal when it is cooled
B. At which new spherical crystals first begin to form from the old deformed one when a strained metal is heated
C. At which change of allotropic form takes place
D. At which crystals grow bigger in size
Answer: B
197. The charge is fed into the blast furnace through the
A. Stack
B. Throat
C. Bosh
D. Tyres
Answer: B
198. 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
199. The property of a material essential for spring materials is
A. Stiffness
B. Ductility
C. Resilience
D. Plasticity
Answer: C
200. Which of the following constituents of steels is softest and least strong?
A. Austenite
B. Pearlite
C. Ferrite
D. Cementite
Answer: C
201. Which of the following is an amorphous material?
A. Mica
B. Silver
C. Lead
D. Glass
Answer: D
202. The following types of materials are usually the most ductile
A. Face centered cubic lattice
B. Body centered cubic lattice
C. Hexagonal close packed lattice
D. All of the above
Answer: A
203. Chromium when added to steel _________ the tensile strength.
A. Does not effect
B. Decreases
C. Increases
D. None of these
Answer: C
204. Pure iron is the structure of
A. Ferrite
B. Pearlite
C. Austenite
D. Ferrite and cementite
Answer: A
205. 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
206. 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
207. In induction hardening ________ is high.
A. Current
B. Voltage
C. Frequency
D. Temperature
Answer: C
208. Paramagnetic alpha iron changes to gamma iron at
A. 770°C
B. 910°C
C. 1440°C
D. 1539°C
Answer: B
209. 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
210. The crystal structure of gamma iron is
A. Body centered cubic
B. Face centered cubic
C. Hexagonal close packed
D. Cubic structure
Answer: B
211. Induction hardening is basically a
A. Carburising process
B. Surface hardening process
C. Core hardening process
D. None of these
Answer: B
212. The crystal of alpha iron is
A. Body centered cubic
B. Face centered cubic
C. Hexagonal close packed
D. Cubic structure
Answer: A
213. Malleable cast iron is produced
A. By adding magnesium to molten cast iron
B. By quick cooling of molten cast iron
C. From white cast iron by annealing process
D. None of these
Answer: C
214. The unique property of cast iron is its high
A. Malleability
B. Ductility
C. Surface finish
D. Damping characteristics
Answer: D
215. Steel containing ferrite and pearlite is
A. Hard
B. Soft
C. Tough
D. Hard and tough
Answer: B
216. Cast iron is characterized by minimum of following percentage of carbon
A. 0.2%
B. 0.8%
C. 1.3%
D. 2%
Answer: D
217. Grey cast iron has
A. Carbon in the form of free graphite
B. High tensile strength
C. Low compressive strength
D. All of these
Answer: A
218. In grey cast iron, carbon is present in the form of
A. Cementite
B. Free carbon
C. Flakes
D. Spheroids
Answer: C
219. In nodular iron, graphite is in the form of
A. Cementite
B. Free carbon
C. Flakes
D. Spheroids
Answer: D
220. In high speed steels, manganese is used to tougher the metal and to increase its
A. Yield point
B. Critical temperature
C. Melting point
D. Hardness
Answer: B
221. In malleable iron, carbon is present in the form of
A. Cementite
B. Free carbon
C. Flakes
D. Nodular aggregates of graphite
Answer: D
222. The purpose of heat treatment is to
A. Relieve the stresses set up in the material after hot or cold working
B. Modify the structure of the material
C. Change grain size
D. Any one of these
Answer: D
223. Wrought iron is
A. Hard
B. High in strength
C. Highly resistant to corrosion
D. Heat treated to change its properties
Answer: C
224. When the steel is normalized, its
A. Yield point increases
B. Ductility decreases
C. Ultimate tensile strength increases
D. All of these
Answer: D
225. Sulphur in pig iron tends to make it
A. Hard
B. Soft
C. Ductile
D. Tough
Answer: A
226. Pick up wrong statement about wrought iron
A. It contains carbon of the order of 0 to 0.25%
B. It melts at 1535°C
C. It is very soft and ductile
D. It is made by adding suitable percentage of carbon to molten iron and subjecting the product to repeated hammering and rolling
Answer: D
227. Combined carbon in iron makes the metal
A. Soft and gives 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
Answer: D
228. Iron is
A. Paramagnetic
B. Ferromagnetic
C. Ferroelectric
D. Dielectric
Answer: B
229. Manganese is added in low carbon steel to
A. Make the steel tougher and harder
B. Raise the yield point
C. Make the steel ductile and of good bending qualities
D. All of the above
Answer: C
230. Chilled cast iron has
A. No graphite
B. A very high percentage of graphite
C. A low percentage of graphite
D. Graphite as its basic constituent of composition
Answer: A
231. The metal suitable for bearings subjected to light loads, is
A. Silicon bronze
B. White metal
C. Monel metal
D. Phosphor bronze
Answer: D
232. Cast iron has
A. High tensile strength
B. Its elastic limit close to the ultimate breaking strength
C. High ductility
D. All of the above
Answer: B
233. Nodular cast iron is produced by adding ________ to the molten cast iron.
A. Nickel
B. Chromium
C. Copper
D. Magnesium
Answer: D
234. 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
235. 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
236. Monel metal is an alloy of
A. Nickel and copper
B. Nickel and chromium
C. Nickel, Chromium and iron
D. Copper and chromium
Answer: A
238. 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
239. Annealing of white cast iron results in production of
A. Malleable iron
B. Nodular iron
C. Spheroidal iron
D. Grey iron
Answer: A
240. The alloying element which can replace tungsten in high speed steels is
A. Nickel
B. Vanadium
C. Cobalt
D. Molybdenum
Answer: D
241. ‘Killed steels’ are those steels
A. Which are destroyed by burning
B. Which after their destruction are recycled to produce fresh steel
C. Which are deoxidized in the ladle with silicon and aluminium
D. In which carbon is completely burnt
Answer: C
242. 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
243. 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
Answer: A
244. Maximum percentage of carbon in ferrite is
A. 0.025%
B. 0.06%
C. 0.1%
D. 0.25%
Answer: A
245. Tungsten when added to steel __________ the critical temperature.
A. Does not effect
B. Lowers
C. Raises
D. None of these
Answer: C
246. 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
247. The material widely used for making pendulums of clocks is
A. Stainless steel
B. High speed steel
C. Heat resisting steel
D. Nickel steel
Answer: D
248. The most effective inhibitor of grain growth, when added in small quantities is
A. Carbon
B. Vanadium
C. Manganese
D. Cobalt
Answer: B
249. The property of a material due to which it breaks with little permanent distortion, is called
A. Brittleness
B. Ductility
C. Malleability
D. Plasticity
Answer: A
250. Depth of hardness of steel is increased by addition of
A. Nickel
B. Chromium
C. Tungsten
D. Vanadium
Answer: B
251. 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
252. Railway rails are normally made of
A. Mild steel
B. Alloy steel
C. High carbon
D. Tungsten steel
Answer: C
253. 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
254. Machining properties of steel are improved by adding
A. Sulphur, lead, phosphorous
B. Silicon, aluminium, titanium
C. Vanadium, aluminium
D. Chromium, nickel
Answer: A
255. The hardness of steel depends upon the
A. Amount of cementite it contains
B. Amount of carbon it contains
C. Contents of alloying elements
D. Method of manufacture of steel
Answer: A
256. Eutectoid steel contains following percentage of carbon
A. 0.02%
B. 0.3%
C. 0.63%
D. 0.8%
Answer: D
257. The electric process of steel making is especially adapted to
A. Alloy and carbon tool steel
B. Magnet steel
C. High speed tool steel
D. All of these
Answer: D
258. The basic constituents of Hastelloy are
A. Aluminium, copper etc.
B. Nickel, molybdenum etc.
C. Nickel, Copper, etc.
D. All of the above
Answer: B
259. German silver contains
A. 1% silver
B. 2% silver
C. 5% silver
D. No silver
Answer: D
260. Basic constituents of Monel metal are
A. Nickel, copper
B. Nickel, molybdenum
C. Zinc, tin, lead
D. Nickel, lead and tin
Answer: A
261. An alloy of copper, tin and zinc is known as
A. Brass
B. Bronze
C. Gun metal
D. Muntz metal
Answer: C
262. German silver is an alloy of
A. Silver and some impurities
B. Refined silver
C. Nickel, Copper and zinc
D. Nickel and copper
Answer: C
263. Quenching is not necessary when hardening is done by
A. Case hardening
B. Flame hardening
C. Nitriding
D. Any one of these
264. 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
265. The alloying element which increases residual magnetism and coercive magnetic force in steel for magnets is
A. Chromium
B. Nickel
C. Vanadium
D. Cobalt
Answer: D
266. A cold chisel is made of
A. Mild steel
B. Cast iron
C. H.S.S.
D. High carbon
Answer: D
267. Blast furnace is used to produce
A. Pig iron
B. Cast iron
C. Wrought iron
D. Steel
Answer: A
268. An engineer’s hammer is made of
A. Cast iron
B. Forged steel
C. Mild steel
D. High carbon steel
Answer: D
269. The blade of a power saw is made of
A. Boron steel
B. High speed steel
C. Stainless steel
D. Malleable cast iron
Answer: B
14. Inconel is an alloy of
A. Nickel, chromium and iron
B. Nickel, copper
C. Nickel, Chromium
D. Nickel, zinc
270. The strength is the ability of a material to resist
A. Deformation under stress
B. Externally applied forces with breakdown or yielding
C. Fracture due to high impact loads
D. None of these
Answer: B
271. By severely deforming a metal in a particular direction it becomes
A. Ductile
B. Malleable
C. Homogeneous
D. Anisotropic
Answer: D
272. Solder is an alloy consisting of
A. Tin, antimony, copper
B. Tin and copper
C. Tin and lead
D. Lead and zinc
Answer: B
273. Iron ore is usually found in the form of
A. Oxides
B. Carbonates
C. Sulphides
D. All of these
Answer: D
274. 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
275. Shock resistance of steel is increased by adding
A. Nickel
B. Chromium
C. Nickel and chromium
D. Sulphur, lead and phosphorus
Answer: C
276. 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
277. 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
278. Process of Austempering results in
A. Formation of bainite structure
B. Carburised structure
C. Martenistic structure
D. Lamellar layers of carbide distributed throughout the structure
Answer: A
279. Hardness of martensite is about
A. RC 65
B. RC 48
C. RC 57
D. RC 80
Answer: A
280. Ball bearings are, usually, made from
A. Low carbon steel
B. High carbon steel
C. Medium carbon steel
D. Chrome steel
Answer: D
281. Weld decay is the phenomenon found with
A. Cast iron
B. Mild steel
C. Nonferrous materials
D. Stainless steel
Answer: D
282. Hardness of upper bainite (acicular structure) is about
A. RC 65
B. RC 48
C. RC 57
D. RC 80
Answer: B
283. Carbon in iron is an example of
A. Substitutional solution
B. Interstitial solid solution
C. Intermetallic compounds
D. All of the above
Answer: B
284. Argentite is the principal ore or raw material for
A. Aluminium
B. Tin
C. Zinc
D. Silver
Answer: D
285. Nimonic contains __________ percentage of nickel as that of Inconel.
A. Same
B. Less
C. More
D. None of these
Answer: A
286. An example of amorphous material is
A. Zinc
B. Lead
C. Silver
D. Glass
Answer: D
287. Which is false statement about tempering? Tempering is done to
A. Improve machinability
B. Improve ductility
C. Improve toughness
D. Release stresses
Answer: A
288. Which of the following is the binding material in cemented carbides?
A. Cobalt
B. Nickel
C. Vanadium
D. Iron
Answer: A
289. Shock resisting steels should have
A. Low wear resistance
B. Low hardness
C. Low tensile strength
D. Toughness
Answer: D
290. Chromium 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 anti-corrosion properties
Answer: A
291. Manganese in steel increases its
A. Tensile strength
B. Hardness
C. Ductility
D. Fluidity
Answer: A
292. Tungsten in high speed steel provides
A. Hot hardness
B. Toughness
C. Wear resistance
D. Sharp cutting edge
Answer: A
293. 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
294. Connecting rod is usually made of
A. Aluminium
B. Low carbon steel
C. Medium carbon steel
D. High carbon steel
Answer: C
295. 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
296. High carbon steel carries carbon percentage
A. 0.1 to 0.3%
B. 0.3 to 0.6%
C. 0.6 to 0.8%
D. 0.8 to 1.5%
Answer: D
297. The hardness of steel increases if it contains
A. Austenite
B. Martensite
C. Pearlite
D. Cementite
Answer: B
298. The presence of sulphur in pig iron makes
A. It easily machinable
B. It brittle
C. It hard
D. The casting unsound
Answer: D
299. Melting point of iron is
A. 1539°C
B. 1601°C
C. 1489°C
D. 1712°C
Answer: A
300. Compressive strength of grey cast iron in tonnes/cm is of the order of
A. 35
B. 57
C. 710
D. 1015
Answer: B
301. Cupola produces following material
A. Cast iron
B. Pig iron
C. Wrought iron
D. Malleable iron
Answer: A
302. Beryllium bronze has
A. High yield point
B. High fatigue limit
C. BothA. andB.
D. None of these
Answer: C
303. 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
304. Drop forging dies contain carbon of the order of
A. 0.1 to 0.2%
B. 0.25 to 0.5%
C. 0.6 to 0.7%
D. 0.7 to 0.9%
Answer: C
305. The alloying element which reduces the formation of iron sulphide in steel is
A. Chromium
B. Nickel
C. Vanadium
D. Manganese
Answer: D
306. Preheating is essential in welding
A. Cast iron
B. High speed steel
C. All nonferrous materials
D. All of the above
Answer: A
307. Steel made from phosphate iron is
A. Brittle
B. Hard
C. Ductile
D. Tough
Answer: A
308. The crystal structure of brass is
A. F.C.C.
B. B.C.C.
C. H.C.P.
D. Orthorhombic crystalline structure
Answer: A
309. 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
310. Which of the following is used for bearing liner?
A. Gun metal
B. Bronze
C. Bell metal
D. Babbitt metal
Answer: D
311. Aluminium bronze contains aluminium and copper in the ratio of
A. 50 : 50
B. 40 : 60
C. 60 : 40
D. 10 : 90
Answer: D
312. Bronze 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 – 75% copper and rest tin
Answer: B
313. 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
314. Perminvar alloy having constant permeability is an alloy of
A. Nickel, copper and iron
B. Nickel, copper and zinc
C. Copper, nickel and antimony
D. Iron, zinc and bismuth
Answer: A
315. The alloy used for making electrical resistances and heating elements is
A. Nichrome
B. Invar
C. Magnin
D. Elinvar
Answer: A
316. Permalloy is a
A. Kind of stainless steel
B. None ferrous alloy
C. Polymer
D. Nickel and iron alloy having high permeability
Answer: D
317. Phosphor bronze contains
A. 0.5% of phosphorous
B. 1% phosphorous
C. 2.5% phosphorous
D. None of the above
Answer: D
318. Free cutting steels
A. Are used where ease in machining is the criterion
B. Contain carbon in free form
C. Require least cutting force
D. Do not exist
Answer: Option
319. Delta metal is an alloy of
A. Copper, zinc and iron
B. Iron, nickel and copper
C. Iron, lead and tin
D. Iron, aluminium and magnesium
Answer: A
320. Addition of copper 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: C
322. Addition of lead and bismuth 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: D
323. Cast iron is a
A. Ductile material
B. Malleable material
C. Brittle material
D. Tough material
Answer: C
324. Addition of silicon 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: A
325. 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
326. German silver contains
A. 1% silver
B. 2.5% silver
C. 5% silver
D. 10% silver
Answer: C
327. Smelting is the process of
A. Removing the impurities like clay, sand etc. from the iron ore by washing with water
B. Expelling moisture, carbon dioxide, sulphur and arsenic from the iron ore by heating in shallow kilns
C. Reducing the ore with carbon in the presence of a flux
D. All of the above
Answer: C
328. Babbitt metal is a
A. Lead base alloy
B. Tin base alloy
C. Copper base alloy
D. BothA. andC. above
Answer: D
329. 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
330. Which of the following material has maximum ductility?
A. Mild steel
B. Copper
C. Nickel
D. Aluminium
Answer: A
331. 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
332. Basic solution is one which has pH value
A. Greater than 7
B. Equal to 7
C. Less than 7
D. pH value has nothing to do with basic solution
Answer: A
333. 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
334. Austenite is a combination of
A. Ferrite and cementite
B. Cementite and gamma iron
C. Ferrite and austenite
D. Ferrite and iron graphite
Answer: B
335. Specify the sequence correctly
A. Grain growth, recrystallization, stress relief
B. Stress relief, grain growth, recrystallization
C. Stress relief, recrystallization, grain growth
D. Grain growth, stress relief, recrystallization
Answer: C
336. The transistor is made of
A. Silver
B. Gold
C. Copper
D. Germanium
Answer: D
337. 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
338. The percentage of carbon in cast iron varies from
A. 0.1 to 0.5
B. 0.5 to 1
C. 1 to 1.7
D. 1.7 to 4.5
Answer: D
339. The hardness and tensile strength in austenitic stainless steel can be increased by
A. Hardening and cold working
B. Normalizing
C. Martempering
D. Full annealing
Answer: A
340. An alloy steel which is work hardenable and which is used to make the blades of bulldozers, bucket wheel excavators and other earth moving equipment contain iron, carbon and
A. Chromium
B. Silicon
C. Manganese
D. Magnesium
Answer: C
341. 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
342. Cast iron is manufactured in
A. Blast furnace
B. Cupola
C. Open hearth furnace
D. Bessemer converter
Answer: B
343. The lower critical point for all steels is
A. 600°C
B. 700°C
C. 723°C
D. 913°C
Answer: C
344. The hardness of steel increases if it contains
A. Pearlite
B. Ferrite
C. Cementite
D. Martensite
Answer: C
345. The cupola is used to manufacture
A. Pig iron
B. Cast iron
C. Wrought iron
D. Steel
Answer: B
346. 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
347. Cartridge brass can be
A. Cold rolled into sheets
B. Drawn into wires
C. Formed into tube
D. Any one of these
Answer: D
348. Which of the following steel making process is being adopted at Rourkela (in India) Steel Plant?
A. Bessemer process
B. Open hearth process
C. Electric process
D. LD process
Answer: D
349. Bronze is an alloy of
A. Copper and zinc
B. Copper and tin
C. Copper, tin and zinc
D. None of these
Answer: B
350. Steel with __________ carbon is known as hypo-eutectoid steel.
A. 0.8%
B. Below 0.8%
C. Above 0.8%
D. None of these
Answer: B
351. Age hardening is related to
A. Duralumin
B. Brass
C. Copper
D. Silver
Answer: A
352. The maximum internal diameter of a blast furnace is about
A. 3 m
B. 6 m
C. 9 m
D. 12 m
Answer: C
353. The machinability of aluminium increases when _________ is added to aluminium.
A. Copper
B. Magnesium
C. Silicon
D. Lead and bismuth
Answer: D
354. Eutectoid reaction occurs at
A. 600°C
B. 723°C
C. 1147°C
D. 1493°C
Answer: B
355. Nickel when added to copper improves
A. Machinability
B. Hardness
C. Hardness and strength
D. Strength and ductility
Answer: B
