1. The eyes of common perception do not see far
The eyes of common perception do not see far. Too often we make the most important decisions based only on superficial information
– Norma Cenva (unpublished laboratory notes)

3. Problem 10.14
List all phases that can be present in steels (do not include the alloy carbide phases or consider stainless steels); describe how each can be formed.
AUS - heat above A1
FE - cool AUS slowly to below A1
CM - cool AUS slowly to below A1
MAR - quench to below ms
(also - liquid & -ferrite)

4. Problem 10.14
For these phases, which can occur in:
hypoeutectoid steels
hypereutectoid steels
a eutectoid steel
AUS, FE, CM, MAR

5. Problem 9.55
Compute fractions of proeutectoid ferrite and pearlite for Fe-0.25C alloy.
Why was this problem assigned?
Understand the terms proeutectoid ferrite and pearlite
Learn to use the equilibrium Fe-C diagram
See that diagram tells amounts of microconstituents
The concept is important; resulting nos. are not (as far as course is concerned)

6. Problem 9.55
Compute fractions of proeutectoid ferrite and pearlite for Fe-0.25C alloy.
Gives proeut. FE fraction:
( )/0.75
= 0.69

7. Problem 9.55 Compute fractions of proeutectoid ferrite and pearlite
proeut. FE fraction = 1

8. Problem 9.55 Compute fractions of proeutectoid ferrite and pearlite
proeut. FE fraction = 0.25
proeut. FE fraction = 0

9. Problem 9.57 Total FE = 0.9, total CM = 0.1. Hypo or hyper?
Why was this problem assigned?
Use the terms hypoeutectoid, hypereutectoid
Total FE, total CM? (where's the beef?)
More contact with Fe-C diagram

10. Problem 9.57 Total FE = 0.9, total CM = 0.1. Hypo or hyper?
Total FE = 0.9 = (6.67-x)/6.65
x = 0.68

11. Problem 10.14
Use TTT curves predict microstructures when steel is cooled as specified
Why was this problem assigned?
Understand TTT curves
Connect cooling process with microstructure
Recognize variety of microstructures possible

12. Problem 10.14
Use TTT curves predict microstructures when steel is cooled as specified
~ 2/3 P, 1/3 MAR
Transformation of AUS not complete till almost 105 s

13. Problem 10.14
Use TTT curves predict microstructures when steel is cooled as specified
Roughly 2/3 bainite + 1/3 MAR

14. Problem 10.14
Use TTT curves predict microstructures when steel is cooled as specified
Tempered MAR