Question:

Surface roughness depends on current density, which is affected by which of the following?

A.

tool feed rate

B.

gap voltage

C.

work piece material

D.

all of the mentioned

Answer» d. all of the mentioned

Question:

Passivation is done on electrolytes in order to form which of the following?

A.

passive layer on machined parts

B.

passive layer on cathode

C.

passive layer on machined parts & cathode

D.

none of the mentioned

Answer» a. passive layer on machined parts

Question:

Tool insulation that                      the side machining action is needed in the process of ECM.

A.

limits

B.

enhances

C.

maintains

D.

none of the mentioned

Answer» a. limits

Question:

If there is an increase in the electrolyte flow, what happens to the rate of film formation?

A.

increases

B.

decreases

C.

remains same

D.

all of the mentioned

Answer» b. decreases

Question:

Nickel can be machined with 100% current efficiency, when current density value is

A.

10 a/cm2

B.

25 a/cm2

C.

45 a/cm2

D.

80 a/cm2

Answer» b. 25 a/cm2

Question:

For large components, actual machining time constitutes to how much percentage of the total machining time?

A.

very low

B.

low

C.

medium

D.

high

Answer» d. high

Question:

Which properties of electrolyte does not affect the accuracy of the process?

A.

temperature

B.

concentration

C.

non-reactive

D.

pressure

Answer» c. non-reactive

Question:

Non stationary behaviour of ECM is due to, which of the factors below?

A.

gas generation

B.

heating

C.

passivation

D.

all of the mentioned

Answer» d. all of the mentioned

Question:

The cost of additional control hardware remain a                    fraction of total machining cost.

A.

small

B.

large

C.

equal

D.

none of the mentioned

Answer» a. small

Question:

When machining Ti, in Nacl electrolyte, what values of current efficiencies are obtained?

A.

10 – 20 %

B.

20 – 30 %

C.

30 – 50 %

D.

50 – 80 %

Answer» a. 10 – 20 %