Mechanical Engineering

Question: In process annealing, the hypo-eutectoid steel is
[A].

heated from 30° C to 50° C above the upper critical temperature and then cooled in still air

[B].

heated from 30° C to 50° C above the upper critical temperature and then cooled suddenly in a suitable cooling medium

[C].

heated from 30° C to 50° C above the upper critical temperature and then cooled slowly in the furnace

[D].

heated below or close to the lower critical temperature and then cooled slowly

Answer: Option D

Explanation:

No answer description available for this question.

Question: In full annealing, the hypo-eutectoid steel is heated from 30° C to 50° C above the upper critical temperature and then cooled
[A].

in still air

[B].

slowly in the furnace

[C].

suddenly in a suitable cooling medium

[D].

any one of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: Which of the following statements are true for annealing of steels?
[A].

Steels are heated to 500 to 700° C

[B].

Cooling is done slowly and steadily

[C].

Internal stresses are relieved

[D].

all of these

Answer: Option D

Explanation:

No answer description available for this question.

Question: In normalising process, the hypo-eutectiod steel is heated from 30° C to 50° C above the upper critical temperature and then cooled in still air.
[A].

True

[B].

False

Answer: Option A

Explanation:

No answer description available for this question.

Question: Normalising of steel is done to
[A].

refine the grain structure

[B].

remove strains caused by cold working

[C].

remove dislocations caused in the internal structuure due to hot working

[D].

all of the above

Answer: Option D

Explanation:

No answer description available for this question.

Question: A steel containing ferrite and pearlite is
[A].

hard

[B].

soft

[C].

tough

[D].

hard and tough

Answer: Option B

Explanation:

No answer description available for this question.

Question: The austenite is a solid solution of carbon or iron carbide in gamma-iron.
[A].

Correct

[B].

Incorrect

Answer: Option A

Explanation:

No answer description available for this question.

Question: Cementite consist of
[A].

13% carbon and 87% ferrite

[B].

13% cementite and 87% ferrite

[C].

13% ferrite and 87% cementite

[D].

6.67% carbon and 93.33% iron

Answer: Option D

Explanation:

No answer description available for this question.

Question: Pearlite consists of
[A].

13% carbon and 87% ferrite

[B].

13% cementite and 87% ferrite

[C].

13% ferrite and 87% cementite

[D].

6.67% carbon and 93.33% iron

Answer: Option B

Explanation:

No answer description available for this question.

Question: An eutectoid steel consists of
[A].

wholly pearlite

[B].

wholly austenite

[C].

pearlite and ferrite

[D].

pearlite and cementite

Answer: Option A

Explanation:

No answer description available for this question.