Engineering Materials

Question: Age hardening is related to
[A].

duralumin

[B].

brass

[C].

copper

[D].

silver

Answer: Option A

Explanation:

No answer description available for this question.

Question: Induction hardening is basically a
[A].

carburising process

[B].

surface hardening process

[C].

core-hardening process

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: In flame hardening, oxy-acetylene flame is used.
[A].

Yes

[B].

No

Answer: Option A

Explanation:

No answer description available for this question.

Question: In induction hardening, the depth of hardening is controlled by controlling the voltage.
[A].

Correct

[B].

Incorrect

Answer: Option A

Explanation:

No answer description available for this question.

Question: In induction hardening __________ is high.
[A].

current

[B].

voltage

[C].

frequency

[D].

temperature

Answer: Option C

Explanation:

No answer description available for this question.

Question: Martensite has needle like structure and is magnetic.
[A].

Correct

[B].

Incorrect

Answer: Option A

Explanation:

No answer description available for this question.

Question: In the austempering process of heat treatment, austenite changes into
[A].

martensite

[B].

troostite

[C].

sorbite

[D].

bainite

Answer: Option D

Explanation:

No answer description available for this question.

Question: A steel is heated at about 875° C where the structure consists of entirely austenite. It is then cooled suddenly at a temperature of about 250° C to 525° C. This process of heat treatment is known as
[A].

normalising

[B].

annealing

[C].

austempering

[D].

martempering

Answer: Option C

Explanation:

No answer description available for this question.

Question: Ferrite and pearlite makes the steel soft and ductile.
[A].

Agree

[B].

Disagree

Answer: Option A

Explanation:

No answer description available for this question.

Question: In a hardening process, 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 B

Explanation:

No answer description available for this question.