MCQs of Allotropy of Iron, Iron-Iron-Carbide equilibrium system (Material Science And Metallurgy - 3131904)

Showing 51 to 60 out of 79 Questions

51.

Free cutting steels

(a)	contain carbon in free from
(b)	require minimum cutting force
(c)	is used where rapid machining is the prime requirement
(d)	can be cut freely

52.

Combined carbon in iron makes the metal

(a)	soft and gives coarse grained crystalline structure
(b)	soft and gives a fine grained crystalline structure
(c)	hard and gives a coarse grained crystalline structure
(d)	hard and gives a fine grained crystalline structure

53.

Free carbon in iron makes the metal

(a)	soft and gives a coarse grained crystalline structure
(b)	soft and gives a fine grained crystalline structure
(c)	hard and gives a coarse grained crystalline structure
(d)	hard and gives a fine grained crystalline structure

54.

The lower critical temperature

(a)	decreases as the carbon content in steel increases
(b)	increases as the carbon content in steel increases
(c)	is same for all steels
(d)	depends upon the rate of heating

55.

A fine grained steel

(a)	is less tough and has a greater tendency to distort during heat treatment
(b)	is more ductile and has a less tendency to distort during heat treatment
(c)	is less tough and has a less tendency to distort during heat treatment
(d)	is more ductile and has a greater tendency to distort during heat treatment

56.

A coarse grained steel

(a)	is less tough and has a greater tendency to distort during heat treatment
(b)	is more ductile and has a less tendency to distort during heat treatment
(c)	is less tough and has a less tendency to distort during heat treatment
(d)	is more ductile and has a greater tendency to distort during heat treatment

57.

Iron-carbon alloys containing 1.7 to 4.3% carbon are known as

58.

A steel with 0.8% carbon is known as

59.

Steel containing 0.8 to 1.5% carbon, is known as

60.

Eutectoid reaction occurs at

Showing 51 to 60 out of 79 Questions