CHEMICAL ENGINEERING

Question: In the acid Bessemer process, the hot metal should have the following com-positon.
[A].

S < 0.05% and P < 0.05%.

[B].

S < 0.05% and P < 1.5%.

[C].

S < 0.05% and P > 1.5%.

[D].

S > 1.5% and P < 0.05%.

Answer: Option A

Explanation:

No answer description available for this question.

Question: Brazing filler metal used for joining steel plates
[A].

melts below the melting points of base metals.

[B].

melts below 300°C.

[C].

is copper phosphorous alloy.

[D].

is copper.

Answer: Option A

Explanation:

No answer description available for this question.

Question: Cold cracking in the heat affected zone of a high strength steel weld can take place because of the
[A].

retained austenite.

[B].

martensite formation.

[C].

relatively high sulphur content in the base metal.

[D].

sufficient hydrogen present in the welding arc.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Internal cracks in drawn bars are due to
[A].

secondary tensile stresses.

[B].

temperature gradient in the work piece.

[C].

heated dies and grips.

[D].

internal compressive residual stress.

Answer: Option A

Explanation:

No answer description available for this question.

Question: In hot working, dynamic recovery occurs in
[A].

metals of low stacking fault energy.

[B].

metals of high stacking fault energy e.g. α-iron.

[C].

single crystal of Ni-based superalloys.

[D].

none of these.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Fine grain size in metallic material will
[A].

increase the yield strength.

[B].

increase the creep strength.

[C].

increase the fatigue strength.

[D].

decrease the impact strength.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Increasing the carbon content of steel
[A].

reduces the upper shelf energy.

[B].

increasing the ductility transition temperature.

[C].

decreases brittleness.

[D].

decreases hardness.

Answer: Option B

Explanation:

No answer description available for this question.

Question: In sheet metal forming, stretcher strains occur in
[A].

duralumin sheets.

[B].

low carbon steel sheets.

[C].

austenitic stainless steel sheets .

[D].

Ni-base alloy sheets.

Answer: Option A

Explanation:

No answer description available for this question.

Question: Pellets are not as popular a burden as sinter in the iron blast furnace, because of their
[A].

shape.

[B].

swelling tendency.

[C].

poor reducibility.

[D].

low mechanical strength.

Answer: Option B

Explanation:

No answer description available for this question.

Question: In TIG welding, thoriated tungsten electrodes are used, because it
[A].

has higher current carraying capacity.

[B].

has better electron emissivity.

[C].

is stronger than ordinary tungsten.

[D].

is easy to prepare.

Answer: Option B

Explanation:

No answer description available for this question.