METALLURGICAL ENGINEERING OBJECTIVE QUESTIONS

1.  As the concentration of point defects in a crystal increases, its configurational entropy
A) does not change
B) decreases
C) increases
D) initially increases and then decreases

2. Critical value of the Gibbs energy of nucleation at equilibrium temperature is

A) zero
B) infinite
C) positive
D) negative

3. With respect to the matrix of Al-Cu alloys, G-P zones are
A) coherent
B) incoherent
C) semi-coherent
D) chemically indistinguishable

4. Which one of the following techniques does NOT require quenching to obtain final case hardness?
A) Flame hardening
B) Induction hardening
C) Nitriding
D) Carburizing


5. Which one of the following elements is an austenite stabilizer?

A) Nitrogen
B) Molybdenum
C) Vanadium
D) Tungsten

6. A 0.2 wt.% plain carbon steel sheet is heated and equilibrated in the inter-critical region followed
by instant water quenching. The microstructure of the quenched steel sheet consists of
A) fully martensite
B) proeutectoid ferrite + martensite
C) martensite + pearlite
D) martensite + austenite

7. As compared to the engineering stress-engineering strain curve, the true stress-true strain curve for
a given material
A) lies above and to the left
B) lies below and to the right
C) crosses the engineering stress-engineering strain curve
D) is identical

8. Which one of the following does NOT improve fatigue life of a steel component?
A) Nitriding
B) Decarburization
C) Improving surface finish
D) Shot-peening


9. In the Ellingham diagram for oxides, C-CO line cuts the M-MO line at temperature T1 and the
M′-M′O line at a higher temperature T2. At a temperature greater than T1 and less than T2, carbon
can reduce
A) MO
B) both MO and M′O
C) M′O
D) neither MO nor M′O

10. A unit cell of an element has maximum linear density along the [110] direction. The packing
density of its (100) plane is
(A) 0.68
B) 0.74
C) 0.79
D) 0.91

11. For an FCC metal, the ratio of interplanar spacing obtained from the first two peaks of the X-ray
diffraction pattern is
(A) 1.91
B) 1.63
C) 1.41
D) 1.15

12. There are 150 gearwheels in a box, out of which 112 are within the required tolerance, 21 are below and rest are above the required tolerance. If the selection is done without replacement, the
combined probability of randomly selecting a gearwheel below the tolerance and then a second one
above the tolerance is

A) 0.016
B) 0.032
C) 0.492
D) 0.984


10. In a roasting process, the set of conditions that favour sulphate formation from metal sulphide
concentrates are
 P. high temperature
 Q. high partial pressure of oxygen
 R. use of excess air
 S. high partial pressure of SO3

A) P, R and S
B) P, Q and R
C) Q and S
D) R and S

11. High top pressure in a blast furnace operation
(A) favours the solution-loss reaction
(B) suppresses the solution-loss reaction
(C) decreases gas-solid contact time
(D) increases coke rate

12. In L-D steelmaking, the final slag can be best described as
A) oxidizing
B) basic
C) oxidizing and basic
D) reducing and basi

13. The permeability of burden in an ironmaking blast furnace can be improved by using
(A) fine charge
(B) agglomerated charge
(C) oxygen enriched air blast
(D) pulverized coal injection through the tuyeres

14. Which one of the following can give information about the corrosion rate?
A) Pourbaix diagram
B) Polarization technique
C) EMF series
D) Galvanic series

15. What is the depth (in m) from the surface of the specimen at which a composition of 0.4 wt.% C is obtained after carburizing at 870°C for 10 h? 
A) 15 
B) 84 
C) 113 
D) 875

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