Material Science MCQ Questions Answers Mechanical Engineering

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11) Atomic packing factor in case of Copper Crystal is

a) 0.52

b) 0.68

c) 0.74

d) 1.633

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12)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

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13) The crystal structure of brass is

a) FCC

b) BCC

c) HCP

d) Orthorhombic

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14) Hardness of martensite is about

a) RC 65

b) RC 48

c) RC 57

d) RC 80

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15) Eutectic product in Fe-C system is called

a) pearlite

b) bainite

c) ledeburite

d) spheroidite

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16) Weight % of carbon in mild steels is

a) <0.008

b) 0.008 – 0.3

c) 0.3 – 0.8

d) 0.8 – 2.11

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17) M_s for Fe-C system is around

a) 725⁰C

b) 550⁰C

c) 450⁰C

d) 210⁰C

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18) Which one of the following elements is a ferritic stabilizer ?

a) Nickel

b) Manganese

c) Copper

d) Chromium

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19) Seasonal cracking is observed in

a) Stainless steel

b) Brass

c) cast iron

d) inconel

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20) Maximum surface hardness is attained by

a) cyaniding

b) carburizing

c) flame hardening

d) nitriding