2651. Delta metal is an alloy of__________________?
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A. iron, lead and tin

B. iron, nickel and copper

C. iron, aluminium and magnesium

D. copper, zinc and antimony

E. copper, zinc and iron
2652. Slow plastic defomiation of metals under a constant stress is known as________________?
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A. creep

B. endurance

C. non-plastic deformation

D. plastic deformation

E. fatigue

2654. Which of the following is used for bearing liner_______________?
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A. gun metal

B. bell metal

C. bronze

D. babbit metal

E. brass

2655. Depth of hardness of steel is increased by addition of_________________?
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A. chromium

B. ell of the above

C. nickel

D. tungsten

E. vanadium

2657. Foundry crucible is made of_________________?
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A. mild steel

B. graphite

C. cast iron

D. lead

E. german silver

2659. Neutral solution is one which has pH value__________________?
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A. none of the above

B. greater than 7

C. pH value has nothing to do with neutral solution

D. less than 7

E. equal to 7
2660. Pick up the wrong statement?
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A. manganese in steel induces hardness

B. nickel and chromium in steel help in raising the elastic limit and improve the resilience and ductility

C. sulphur, phosphorous and lead improve machining properties of steel

D. tungsten in steels improves magnetic properties and hardenability

E. aluminium in steel results in excessive grain growth
2661. Nickel in steel___________________?
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A. improves wear resistance, cutting ability and toughness

B. improves cutting ability and reduces hardenability

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

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

E. none of the above

2662. The metallic structure of mild steel is_________________?
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A. orthorhombic crystal

B. face centred cubic

C. body centred cubic

D. hexagonal close packed

E. cubic structure

2665. Annealing of white cast iron results in production of_________________?
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A. grey iron

B. spheroidal iron

C. none of the above

D. nodular iron

E. malleable iron
2668. Which of the following has highest specific strength of all structural materials__________________?
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A. chromium alloys

B. none of the above

C. titanium alloys

D. magnesium alloys

E. magnetic steel alloys

2669. An engineers hammer is made of___________________?
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A. forged steel

B. high carbon steel

C. cast iron

D. mild steel

E. H.S.S

2670. Pearlite is a combination of___________________?
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A. ferrite and cementite

B. cementite and gamma iron

C. pearlite and ferrite

D. ferrite and iron graphite

E. ferrite and austenite

2671. Malleable cast iron _________________?
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A. contains l.7 to 3.5% carbon in free state and is obtained by the slow cooling of molten cast iron

B. none of the above

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

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

E. is produced by annealing process. It is soft, tough, and easily machined metal
2672. In mottled cast iron, carbon is available in__________________?
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A. nodular form

B. flat form

C. combined form

D. free form

E. partly in free and partly in combined state
2673. Weld decay is the phenomenon found with _________________?
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A. wrought iron

B. non-ferrous materials

C. mild steel

D. cast iron

E. stainless steel
2674. The ultimate tensile strength of low carbon steel by working at a high strain rate will_________________?
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A. increase

B. decrease

C. first decrease and then increase

D. first increase and then decrease

E. remain constant

2675. Addition of lead and bismuth 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

2677. Drop forging dies contain carbon of the order of_________________?
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A. 0.6 to 0.7%

B. 0.25 to 0.5%

C. 0.7 to 0.9%

D. 0.1 to 0.2%

E. 1.0 to 1.2%.

2678. Delta iron occurs at temperature of_______________?
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A. above melting point

B. between 1400C and 1539C

C. between 910C and 1400C

D. room temperature

E. none of the above

2679. The machinability of steel is increased by___________________?
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A. silicon and sulphur

B. none of the above

C. phosphorous, lead and sulphur

D. sulphur, graphite and aluminium

E. phosphorous and aluminium

2681. Corrosion resistance of steel is increased by addition of________________?
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A. zinc

B. sulphur, phosphorus, lead

C. chromium and nickel

D. vanadium, aluminium

E. tungsten, molybdenum, vanadium, chromium

2682. Tungsten in steel________________?
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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 anticorrosion properties

E. raises its melting point

2683. White cast iron__________________?
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A. is produced by annealing process. It is soft, tough and easily machined metal

B. none of the above

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

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

E. 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

2684. The transistor is made of___________________?
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A. germanium

B. german silver

C. copper

D. silver

E. gold

2685. Tungsten in high speed steel provides________________?
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A. cold hardness

B. toughness

C. wear resistance

D. hot hardness

E. sharp cutting edge

2686. The tensile strength of wrought iron is maximum _________________?
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A. along the lines of slag distribution

B. uniform in all directions

C. none of the above

D. perpendicular to lines of slag distribution

E. unpredictable

2687. Austenite rs a combination of_________________?
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A. ferrite and iron graphite

B. pearlite and ferrite

C. ferrite and austenite

D. ferrite and cementite

E. cementite and gamma iron
2689. Nodular iron has____________________?
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A. all of the above

B. high maehinability

C. low melting point

D. good fluidity

E. high tensile strength

2690. Structural steel contains following principal alloying elements__________________?
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A. zinc, sulphur, and chromium

B. nickel, chromium and manganese

C. none of the above

D. tungsten, molybdenum and phosphorous

E. lead, tin, aluminium

2691. Free cutting steels_____________________?
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A. contain carbon in free form

B. require least cutting force

C. are used where ease in machining is the criterion

D. can be cut freely even under adverse conditions

E. do not exist

2692. Which is false statement about annealing. Annealing is done to________________?
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A. harden steel slightly

B. permit further cold working

C. soften material

D. relieve stresses

E. improve machining characteristic

2693. The usual composition of a soldering alloy is__________________?
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A. tin and lead

B. tin, lead and silver

C. tin, copper and lead

D. tin, lead and small percentage of antimony

E. tin and copper

2694. Gun metal contains__________________?
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A. 85-92% copper and rest tin with little lead and nickel

B. 85-92% copper and rest zinc

C. 90% copper and 10% tin

D. 70-78% copper and rest tin

E. 70% copper and 30% zinc

2695. A specimen of aluminium metal when observed under microscope shows __________________?
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A. a complex cubic structure

B. F.C.C. crystal structure

C. B.C.C. crystalline structure

D. H.C.P. structure

E. orthorhombic crystalline structure

2696. Pig iron is the name given to________________?
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A. product of blast furnace made by reduction of iron ore

B. iron scrap

C. raw material for blast furnace

D. iron in molten form in the ladles

E. iron containing huge quantities of carbon

2697. Grey cast iron_____________________?
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A. is also known as chilled cast iron am is obtained by cooling rapidly. It i: almost unmachinable

B. is produced by small additions o magnesium (or cerium) in the ladle Graphite is in nodular or spheroida form and is well dispersed throughout the material

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

D. is produced by annealing process. I is soft, tough and easily machinec metal

E. none of the above is true

2698. Brass contains___________________?
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A. 70-75% copper and rest tin

B. 90% copper and 10% tin

C. 85-92% copper and rest tin with little lead and nickel

D. 70% copper and 30% zinc

E. 70% copper and 30% tin

2699. Basic constituents of Monel metal are _________________?
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A. zinc, tin, lead

B. nickel, lead and tin

C. nickel, molybdenum

D. nickel, copper

E. none of the above

2700. Corrundum contains more than 95% _____________________?
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A. steel

B. A1203

C. MgO

D. german silver

E. Si02