MCQ
661. Solder is an alloy consisting of--
tin, antimony, copper
tin and lead
tin and copper
lead and zinc
662. The percentage of carbon in low carbon steel is—
0.05%
0.15%
0.3%
0.5%
663. Austenite is a combination of--
ferritc and cementite
cementite and gamma iron
ferrite and austenite
ferrite and iron graphite
664. 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
665. Steel containing 0.8 to 1.5% carbon is known as—
mild steel
medium carbon
dead mild steel
high carbon steel
666. The percentage carbon content in wrought iron is about--
0.02
0.2
0.1
0.4
667. Basic constituents of Monel metal are--
nickel, copper
nickel, molybdenum
zinc, tin, lead
nickel, lead and tin
668. 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
669. Ductile cast iron—
contains 1.7 to 3.5% carbon in free state and is obtained by the slow cooling of molten cast iron
is also known as chilled cast iron and is obtained by cooling rapidly. It is almost non-machinable
is produced by annealing process. It is soft, tough and easily machined metal
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
670. Inconel is an alloy of--
nickel, chromium and iron
nickel, copper
nickel, chromium
nickel, zinc
671. Nickel in steel—
improves wear resistance, cuttinability and toughness
refines grain size and produces les tendency to carburisation, improve corrosion and heat resistant proper ties
improves cutting ability and reduce hardenability
gives ductility, toughness, tensile strength and anti-corrosion property
672. Cobalt in steel—
improves wear resistance, cuttinability and toughness
refines grain size and produces les tendency to carburisation, improve corrosion and heat resistant proper ties
improves cutting ability and reduce hardenability
gives ductility, toughness, tensile strength and anti-corrosion property
673. Grey cast iron--
contains 1.7 to 3.5% carbon in free state and is obtained by the slow cooling of molten
is also known as chilled cast iron and is obtained by cooling rapidly. It is almost non-machinable
is produced by annealing process. It is soft, tough and easily machine metal
is produced by small additions of magnesium (or cerium) in the ladle. Graphite is in nodular or spheroida form and is well dispersed throughout the material
674. Eutectoid steel contains following percentage of carbon—
0.02%
0.3%
0.63%
0.8%
675. A steel alloy containing 36% nickel is called--
stainless
invar
high speed steel
heat resenting steel
676. 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
677. The transistor is made of--
silver
gold
copper
germanium
678. Nodular iron has--
high machinability
low melting point
high tensile strength
all of the above.
679. Machining properties of steel are improved by adding--
sulphur, lead, phosphorous
silicon, aluminium, titanium
vanadium, aluminium
chromium, nickel
680. The basic constituents of Hastelloy are--
aluminium, copper etc.
nickel, molybdenum etc.
nickel, copper, etc
all of the above