Chemical Engineering Basics

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.

Question: During solid state sintering of powders, the following mechanism can be active.
[A].

Evaporation and condensation.

[B].

Solid state diffusion processes.

[C].

Liquid formation in grain boundaries.

[D].

Creation of more dislocations.

Answer: Option B

Explanation:

No answer description available for this question.

Question: A simple closed grinding circuit may consist of
[A].

a ball mill and a classifier.

[B].

a rod mill and a hydrocyclone.

[C].

a jaw crusher and a hydrocyclone.

[D].

a ball mill and a froth floatation cell.

Answer: Option A

Explanation:

No answer description available for this question.

Question: Fatigue life is expected to increase by
[A].

increasing the size of the sample.

[B].

smooth polishing of the surface of the sample.

[C].

having compressive residual stresses at the surface.

[D].

having tensile residual stresses at the surface.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Cementite is in the lamellar form in the __________ phase of steel.
[A].

martensitic

[B].

bainitic

[C].

pearlitic

[D].

ferritic

Answer: Option C

Explanation:

No answer description available for this question.