Engineering Questions with Answers - Multiple Choice Questions
Materials Science MCQ’s – Time Temperature Transformation(TTT) Curves
1 - Question
Time temperature transformation diagrams are drawn for ______________
a) Iron
b) Manganese
c) Any alloy
d) Only steel
View Answer
Explanation: Time temperature transformation diagrams are drawn for only steels and only on steel of constant composition at a time is taken.
2 - Question
Which of the following is not a name for time temperature transformation diagrams?
a) S curve
b) C curve isothermal diagram
c) D curve isothermal diagram
d) Bain’s curve
View Answer
Explanation: S curve, C curve isothermal diagram and Bain’s curve are all names given to time temperature transformation diagrams. D curve isothermal diagram is not a name given to it.
3 - Question
Steel with different carbon content shows different time temperature transformation diagrams.
a) True
b) False
View Answer
Explanation: The above statement is true. Steel with different carbon content shows different time temperature transformation diagrams.
4 - Question
Which of the following phase will be resulted when the transformation temperature of steel is more than 750 °C?
a) Austenite
b) Pearlite
c) Bainite
d) Martensite
View Answer
Explanation: At a temperature above 750 °C, the steel is in the form of austenite which is observed from a time temperature transformation diagram which shows the transformation time and temperature of transformation.
5 - Question
Which of the following phase will be resulted when the transformation temperature of steel is in the range of 500 °C to 750 °C?
a) Austenite
b) Pearlite
c) Bainite
d) Martensite
View Answer
Explanation: At a temperature between 550 °C and 750° C, the steel is in the form of pearlite which is observed from a time temperature transformation diagram which shows the transformation time and temperature of transformation.
6 - Question
Which of the following phase will be resulted when the transformation temperature of steel is in the range of 300 °C to 550 °C?
a) Austenite
b) Pearlite
c) Bainite
d) Martensite
View Answer
Explanation: At a temperature between 300 °C and 550°C, the steel is in the form of bainite which is observed from a time temperature transformation diagram which shows the transformation time and temperature of transformation.
7 - Question
Which of the following phase will be resulted when the transformation temperature of steel is in the range of 100 °C to 300 °C?
a) Austenite
b) Pearlite
c) Bainite
d) Martensite
View Answer
Explanation: At a temperature 100 °C and 300°C, the steel is in the form of martensite which is observed from a time temperature transformation diagram which shows the transformation time and temperature of transformation.
8 - Question
Which of the following is the hardest?
a) Austenite
b) Pearlite
c) Bainite
d) Martensite
View Answer
Explanation: Martensite is the hardest among the four followed by bainite and then pearlite. Austenite is the least hard among the following as it occurs at the highest temperature where the steel is soft.
9 - Question
To construct a TTT diagram, the specimen of steels is heated and then cooled.
a) True
b) False
View Answer
Explanation: The above statement is true. To construct a time temperature transformation diagram, the specimen of steels is heated to a fixed temperature and then rapidly cooled.
10 - Question
In an isothermal curve, which of the following is true when the temperature is increased?
a) The curve shifts rightward
b) The curve shifts leftward
c) The curve goes down
d) The curve goes up
View Answer
Explanation: In an isothermal curve with an increase in temperature the curve shifts towards the right and with a decrease in temperature the curve will shift towards left on the graph.