Engineering Questions with Answers - Multiple Choice Questions
Materials Science MCQ’s – Cast Irons
1 - Question
Which of the following can be carbon composition of cast iron?
a) 1%
b) 1.5%
c) 0.5%
d) 2.5%
View Answer
Explanation: The carbon composition in cast iron is more than 2% and hence only 2.5% can be correct answer as all the answer lie outside the range.
2 - Question
Cast iron tends to be brittle.
a) True
b) False
View Answer
Explanation: The above statement is correct. Cast iron tends to be brittle because of the presence of a high amount of carbon in it.
3 - Question
At what temperature does pure iron turn into FCC structure?
a) 800 °C
b) 900 °C
c) 910 °C
d) 810 °C
View Answer
Explanation: Pure iron turns into its FCC structure at a temperature of 910 °C. This structure is called gamma iron or γ-iron.
4 - Question
Which of the following alloying element forces the carbon out of the solution?
a) Silicon
b) Sulphur
c) Nickel
d) Titanium
View Answer
Explanation: Silicon is used in a cast iron to bring out the carbon from the solution. If a large amount silicon is added grey cast iron is formed.
5 - Question
Which of the following alloying element increase hardness?
a) Silicon
b) Sulphur
c) Nickel
d) Titanium
View Answer
Explanation: The presence of sulfur increase the hardness of the alloy by reacting with iron to form iron sulphide.
6 - Question
Which of the following alloying element refines pearlite structure?
a) Silicon
b) Sulphur
c) Nickel
d) Titanium
View Answer
Explanation: Nickel is the most common alloying element in cast iron. It helps in refining the pearlite and graphite structure.
7 - Question
Which of the following alloying element is added as a degasser?
a) Silicon
b) Sulphur
c) Nickel
d) Titanium
View Answer
Explanation: Titanium is added as a degasser and it increases the fluidity of the alloy and it also acts as a deoxidiser.
8 - Question
Due to the presence of which of the following does white cast iron appear white?
a) Pearlite
b) Ledeburite
c) Martensite
d) Cementite
View Answer
Explanation: In white cast iron, it appears as a broken white surface due to the presence of cementite which is a metastable phase.
9 - Question
In malleable cast iron, the graphite turns into spheroidal particles.
a) True
b) False
View Answer
Explanation: The above statement is true. In malleable cast iron, the graphite turns into spheroidal particles rather than forming flakes.
10 - Question
What is the form graphite structure in ductile cast iron?
a) Spheroidal
b) Nodular
c) Flakes
d) Layers
View Answer
Explanation: The graphite structure of a ductile cast iron is nodular form and it is seen as tiny nodules with graphite in layers forming the nodules.