Mechanical Engineering - Engineering Materials

31. 

Micro-structure of a material is, generally, examined by

A. naked eye
B. optical microscope
C. X-ray techniques
D. none of these

Answer: Option D

Explanation:

No answer description available for this question. Let us discuss.

32. 

The addition of magnesium to cast iron increases its

A. hardness
B. ductility and strength in tension
C. corrosion resistance
D. creep strength

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.

33. 

Killed steels

A. have minimum impurity level
B. are produced by L-D process
C. have almost zero percentage of phosphorus and sulphur
D. are free from oxygen

Answer: Option D

Explanation:

No answer description available for this question. Let us discuss.

34. 

The slow cooling of steel from the __________ results in a coarse grained structure.

A. lower critical point
B. upper critical point

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.

35. 

Which one of the following sets of constituents is expected in equilibrium cooling of a hyper-eutectoid steel from austenitic state?

A. Ferrite and pearlite
B. Cementite and pearlite
C. Ferrite and bainite
D. Cementite and martensite

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.