মেটালার্জি MCQ
61. Silicon in cast iron-
Incrouse hardness and brittleness
Maker the iron write and hard
Aids fusibility and fluidity
Makes the iron soft and easily Machinable
62. Taps, dies and drills contain carbon-
below 0.5%
below 1%
above 1%
above 2.2%
63. Nodular cast iron is produced by adding the molten cast iron-
Nickel
Copper
Chromium
Magnesium
64. A steel with carbon is --known as hyper- eutectoid steel--
0.87%
below 0.8%
above 0.8%
None of them
65. Iron carbon alloy containing carbon --4.3% carbon are known as hyper-eutectic cast Irons.
usual to
more than
less than
none of them
66. Drop forging dies contain carbon of the order of --
0.1 to 0.2%
0.25 0.5%
0.6 to 0.7%
0.7 to 0.9%
67. Following elements have face-centred cubic structure—
gamma iron (910° to 1400°C), Cu, Ag, Au, Al, Ni, Pb, Pt
Mg, Zn. Ti. Zr, Br, Cd
a iron (below 910°C and between1400 10 1539°C), W
all of the above
68. What is used as joining medium in brazing operation?
Copper-Zinc alloy
Lead-Tin alloy
Nickel-Silver alloy
All of the above
69. Steel containing 0.8 to 1.5% carbon is known as—
mild steel
medium carbon
dead mild steel
high carbon steel
70. In the lower part of the blast furnace (Zone of fusion) the temperature is—
800-1000°C
1500-1700°C
400-700°C
1200-1300°C
71. The correct composition of Babbit metal is—
87.75% Sn, 4% Cu, 8% Sb. 0.25% Bi
90% Sn, 2% Cu, 4% Sb. 2% Bi, 2% Mg
87% Sn, 4% Cu, 8% Sb, 1% Al
82% Sn, 4% Cu, 8% Sb, 3% Al. 35% Mg
72. The percentage carbon content in wrought iron is about--
0.02
0.2
0.1
0.4
73. Muntz metal (yellow brass) contains—
70% copper and 30% zinc
60% copper and 40% zinc
60% copper and 30% zinc
60.45% copper, 35.2% zinc and 5.35% nickel
74. The material commonly used for machine tool bodies is-.
mild steel
brass
aluminium
cast iron
75. Duralumin contains—
94% aluminium, 4% copper and 0.5% Mn. Mg. Si and Fe
10% aluminiunt and 90% copper
90% magnesium and alumunium with some copper
92.5% aluminium, 40% copper, 2%, nickel, and 1.5% Mg
76. The austenitic stainless steel centrums-
18% chromium and 8% nickel
8% chromium and 18% nickel
14% nickel and 0.35% carbon
14% nickel and 0.35% carbon
77. Which of the following impunity in the cast iron promoter graphite module formation and increase the fluidity of the molten metal?
Sulphur
Manganese
Phorphorus
Silicon
78. A steel alloy containing 36% nickel is called--
stainless
invar
high speed steel
heat resenting steel
79. The carbon in the pig iror varier from-
0.1 to 0.5%
1 to 5 %
0.5 to 15%
5 to 10%
80. Which is binding material?
Sand
Cement
Khoa
Rod