2601. Wrought iron is________________?
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A. least resistant to corrosion

B. high in strength

C. heat treated to change its properties

D. highly resistant to corrosion

E. hard

2602. Railway rails are normally made of_______________?
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A. cast iron steel

B. tungsten steel

C. high carbon

D. alloy steel

E. mild steel

2603. Cast iron has_________________?
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A. none of the above

B. high ductility

C. high tensile strength

D. its elastic limit close to the ultimate breaking strength

E. all of the above

2604. Chromium in steel_________________?
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A. makes steel hard

B. refines grain size and produces less tendency to carburisation, improves corrosion and heat resistant properties

C. gives ductility, toughness, tensile strength and anticorrosion properties

D. improves wear resistance, cutting ability and toughness

E. improves cutting ability and reduces hardenability

2605. The correct sequence for descending order of machinability is _____________________?
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A. grey cast iron, wrought iron, low carbon steel

B. grey cast iron, low carbon steel, wrought iron

C. wrought iron,low carbon steel, grey cast iron

D. low carbon steel, grey cast iron, wrought iron

E. wrought iron, grey cast iron, low carbon steel

2606. Pure iron is the structure of_______________?
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A. pearlite

B. ferrite

C. ferrite and cementite

D. ferrite and pearlite

E. anstenite

2607. The molecules in a solid move______________?
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A. in a haphazard way

B. in circular motion

C. do not move

D. in a random manner

E. back and forth like tiny pendulums
2608. Which of the following alloys does not contain tin_________________?
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A. gun metal

B. phosphor bronze

C. white metal

D. fusible metal

E. solder admiralty

2609. Ductile cast iron___________________?
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A. is produced by annealing process. It is soft, tough and easily machined metal

B. 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

C. none of the above

D. contains 1.7 to 3.5% carbon in free state and is obtained by the slow cooling of molten cast iron

E. is also known as chilled cast iron and is obtained by cooling rapidly. It is almost unmachinable

2610. Tensile strength of steel can be safely in-creased by________________?
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A. adding carbon up to 0.83%

B. adding copper and carbon

C. adding carbon up to 6.3%

D. adding small quantities of copper

E. adding carbon up to 2.8%

2611. Perminvar alloy having constant permeability is an alloy of________________?
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A. copper, nickel and antimony

B. iron, zinc and bismuth

C. antimony, copper and zinc

D. nickel, copper and iron

E. nickel, copper and zinc

2612. Pipes for bicycle frames are made of___________________?
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A. forged steel

B. hot rolled steel

C. cold rolled steel

D. carbon-chrome steel

E. cast steel

2613. Carbon steel is_______________?
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A. an alloy of iron and carbon with varying quantities of phosphorus and sulphur

B. extremely brittle

C. made by adding carbon in steel

D. extensively used for making cutting tools

E. refined from cast iron

2614. Steel contains____________________?
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A. high quantities of sulphur

B. alloying elements like chromium, tungsten nickel and copper

C. 50% or more iron

D. 80% or more iron

E. elements like phosphorus, sulphur and silicon in varying quantities

2615. Acidic solution is one which has pH value__________________?
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A. less than 7

B. equal to 7

C. pH value has nothing to do with neutral solution

D. greater than 7

E. none of the above

2616. An important property of malleable cast iron in comparison to grey cast iron is the high___________________?
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A. ductility

B. compressive strength

C. surface finish

D. hardness

E. carbon content

2617. Addition of silicon to aluminium results in____________________?
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A. none of the above

B. improvement of casting characteristics

C. one of the best known age and precipitation-hardening systems

D. improvement of corrosion resistance

E. improving machinability

2618. Preheating is essential in welding ___________________?
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A. high speed steel

B. none of the above

C. all of the above

D. all non-ferrous materials

E. cast iron
2619. The crystal structure of brass is_________________?
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A. H.C.P.

B. B.C.C.

C. Orthorhombic crystalline structure

D. none of the above

E. F.C.C.
2620. Large forgings, crank shafts, axles normally contain carbon up to________________?
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A. 0.45 to 0.55%

B. 0.05 to 0.20%

C. 1.0 to 1.2%.

D. 0.55 to 1.0%

E. 0.20 to 0.45%

2621. Constantant an alloy used in thermocouples is an alloy of __________________?
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A. copper and nickel

B. copper and iron

C. copper and chromium

D. copper and zinc

E. copper and tin

2622. Paramagnetic alpha iron changes to gamma iron at_______________?
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A. none of the above

B. 770C

C. 1539C

D. 1440C

E. 910C
2623. Hardness of martensite is about___________________?
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A. RC 48

B. RC 80

C. RC 65

D. RC 32

E. RC 57

2624. Inconel is an alloy of___________________?
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A. nickel, chromium

B. nickel, chromium and iron

C. nickel, zinc

D. nickel, lead

E. nickel, copper

2625. A cold chisel is made of_______________?
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A. mild steel

B. german silver

C. H.S.S.

D. high carbon

E. cast iron

2626. Muntz metal contains copper and zinc in the ratio of________________?
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A. 40 : 60

B. 50:50:00

C. 60 : 40

D. 0.888888889

E. 80:20:00

2627. Addition of manganese to aluminium results in__________________?
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A. improvement of casting characteristics

B. none of the above

C. improving machinability

D. improvement of corrosion resistance

E. one of the best known age and precipitation-hardening systems

2628. In nodular iron, graphite is in the form of_____________________?
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A. spheroids

B. cementite

C. free carbon

D. flakes

E. nodular aggregates of graphite

2629. Which is false statement about normalizing. Normalizing is done to _________________?
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A. refine grain structure

B. reduce segregation in casting

C. induce stresses-

D. relieve internal stresses

E. improve mechanical properties

2631. Process of austempering results in__________________?
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A. carburised structure

B. formation of bainite structure

C. lamellar layers of carbide distributed throughout the structure

D. relieving of stresses throughout a component

E. martenistic structure

2633. Corrosion resistance of steel is increased by adding__________________?
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A. tungsten and sulfur

B. none of the above

C. nickel and molybdenum

D. chromium and nickel

E. aluminium and zinc

2634. The crystal structure of gamma iron is_________________?
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A. orthorhombic crystal

B. face centred cubic

C. cubic structure

D. hexagonal close packed

E. body centred cubic

2635. The correct composition of Babbit metal is__________________?
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A. 90% Sn, 2% Cu, 4% Sb, 2% Bi, 2% Mg

B. 82% Sn, 4% Cu, 8% Sb, 3% Al, 3% Mg

C. 87% Sn, 4% Cu, 8% Sb, 1% Al

D. none of the above

E. 87.75% Sn, 4% Cu, 8% Sb, 0.25% Bi
2636. The presence of sulphur in pig iron makes__________________?
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A. it hard

B. it brittle

C. the casting unsound

D. it easily machinable

E. increases the fluidity

2638. Melting point of iron is__________________?
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A. 1539C

B. 1601C

C. 1489C

D. 1131C

E. 1712C

2639. Which of the following alloys does not have copper as one of the constituents________________?
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A. constantan

B. delta metal

C. nichrome

D. monel metal

E. silicon bronze

2641. Chilled cast iron has____________________?
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A. none of the above is true

B. a low percentage of graphite

C. no graphite

D. a very high percentage of graphite

E. graphite as its basic constituent of composition

2642. Carbon in iron is an example of__________________?
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A. interstitial solid solution

B. none of the above.

C. substitutional solution

D. intermetallic compounds

E. all of the above

2643. Super conduction by metals is observed in the temperature range of_________________?
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A. below 10K

B. above 100K

C. above 1000C

D. around 0C

E. around 100C

2644. Materials after cold working are subjected to following process to relieve stresses__________________?
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A. annealing

B. hot working

C. tempering

D. normalising

E. special heat treatment

2645. DuraJomin contains___________________?
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A. 90% magnesium and 9% aluminium with some copper

B. 92.5% aluminium, 40% copper, 2% nickel, and 1.5% Mg

C. 94% aluminium, 4% copper and 0.5% Mn, Mg, Si and Fe

D. 10% aluminium and 90% copper

E. 94% aluminium and 6% tin

2646. Iron is ____________________?
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A. ferroelectric

B. dielectric

C. paramagnetic

D. none of the above

E. ferromagnetic
2647. The elastic stress strain behaviour of rubber is_____________________?
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A. no fixed relationship

B. non-linear

C. linear

D. unpredictable behaviour

E. plastic

2648. White metal contains__________________?
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A. alloy of tin, lead and cadmium

B. malleable cast iron and silver

C. silver and chromium

D. 88% copper and 10% tin and rest zinc

E. 63 to 67% nickel and 30% copper

2649. The following types of materials are usually the most ductile__________________?
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A. face-centred cubic lattice

B. hexagonal close-packed lattice

C. none of the above

D. all of the above

E. body-centred cubic lattice