Manufacturing Engineering Questions & Answers – Iron Carbon Phase Diagram-1

«
»

This set of Manufacturing Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Iron Carbon Phase Diagram-1”.

1. The melting point of iron (in oC) is?
a) 768
b) 1535
c) 1410
d) 910
View Answer

Answer: b
Explanation: Melting point of iron in degree centigrade is 1535oC.
advertisement

2. Iron-Carbon phase diagram is a ___________
a) Unary phase diagram
b) Binary phase diagram
c) Tertiary phase diagram
d) Ternary phase diagram
View Answer

Answer: b
Explanation: Binary phase diagrams are based on two component systems. Here, the two components may be mixed in an infinite number of different proportions, which indicates that composition also becomes a variable, along with pressure and temperature. Iron-carbon phase diagram, Pb-Sn diagram are the best examples of this category.

3. The temperature (in oC) of peritectic reaction in iron-carbon phase diagram is?
a) 1539
b) 1493
c) 910
d) 1175
View Answer

Answer: b
Explanation: The invariant peritectic reaction (while cooling) in Fe-C phase diagram is given by:
L (0.53%C) + δ-ferrite (BCC, 0.09%C) \(_{\overrightarrow{1493^o C}}\) γ (FCC, 0.17%C)
advertisement
advertisement

4. The temperature (in oC) of eutectic reaction in iron-carbon phase diagram is?
a) 1539
b) 1493
c) 910
d) 1150
View Answer

Answer: d
Explanation: The invariant eutectic reaction (while cooling) in Fe-C phase diagram is given by:
L (4.3%C) \(_{\overrightarrow{1150^o C}}\) γ (FCC, 2.11%C) + Cementite (Orthorhombic, 6.67%C)

5. The temperature (in oC) of eutectoid reaction in iron-carbon phase diagram is?
a) 1120
b) 725
c) 910
d) 820
View Answer

Answer: b
Explanation: The invariant peritectoid reaction (while cooling) in Fe-C phase diagram is given by
γ (FCC, 0.77%C) \(_{\overrightarrow{725^o C}}\)Ferrite (BCC, 0.02%C)+ Cementite (Orthorhombic, 6.67%C).
advertisement

6. The percentage of carbon at eutectic point in Fe-C phase diagram is?
a) 2.1
b) 4.3
c) 0.83
d) 0.02
View Answer

Answer: b
Explanation: The lowest melting alloy, the Fe-4.3% C alloy is called eutectic cast iron. This is a single-phase liquid (100%) of 4.3% carbon at the eutectic temeprature 1150oC.

7. The percentage of carbon at eutectoid point in Fe-C phase diagram is?
a) 2.1
b) 4.3
c) 0.83
d) 0.02
View Answer

Answer: c
Explanation: During cooling, austenite of 0.77% C, at a temeprature 725oC undergoes eutectoid transformation and forms a eutectoid a mixture of ferrite and cementite, known as pearlite.
advertisement

8. The percentage of carbon at peritectic point in Fe-C phase diagram is?
a) 2.1
b) 4.3
c) 0.83
d) 0.18
View Answer

Answer: d
Explanation: Percentage of carbon at peritectic point = 0.18%. Peritectic reaction in iron-carbon phase diagram takes place at constant temperature of 1493oC.

9. Which of the following reaction does not exhibit mushy zone in Fe-C phase diagram?
a) Eutectic reaction
b) Peritectic reaction
c) Eutectoid reaction
d) Peritectoid reaction
View Answer

Answer: a
Explanation: A mushy zone is nothing but a solid-liquid mix in a two-phase region. The alloys or reactions, which exhibits lower melting points than the two pure metals are known as eutectic alloy systems taking eutectic reaction does not exhibit mushy zone.
advertisement

10. γ form of iron is?
a) Magnetic
b) Non magnetic
c) Occurs below 768oC
d) Occurs above 1410oC
View Answer

Answer: a
Explanation: γ form of iron is known as austenite (named after ‘Sir Austin), which is an interstitial solid solution of carbon in FCC iron. Austenite is soft, ductile, tough, malleable and non-magnetic.

Sanfoundry Global Education & Learning Series – Manufacturing Engineering.

To practice all areas of Manufacturing Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.

Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

advertisement
advertisement
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He is Linux Kernel Developer & SAN Architect and is passionate about competency developments in these areas. He lives in Bangalore and delivers focused training sessions to IT professionals in Linux Kernel, Linux Debugging, Linux Device Drivers, Linux Networking, Linux Storage, Advanced C Programming, SAN Storage Technologies, SCSI Internals & Storage Protocols such as iSCSI & Fiber Channel. Stay connected with him @ LinkedIn | Youtube | Instagram | Facebook | Twitter