1. Simultaneous Transformation Kinetics
Avrami theory
Adapted for many reactions occurring together
Ferrite, Widmanstatten ferrite, pearlite….
Complex carbide-precipitation reactions
Competition between inter- and intra-granularly nucleated reactions
Some difficulties

2. DISPLACIVE
RECONSTRUCTIVE

3. PREDICTED FRACTION MEASURED FRACTION 1.00 Allotriomorphic
Widmanstatten
Pearlite
0.75
0.50
0.25
0.00
0.00
0.25
0.50
0.75
1.00
MEASURED FRACTION
Jones & Bhadeshia, 1996

4.     
CONSTRAINED
UNCONSTRAINED

5.   11 K/min 101 K/min Temperature / °C
0.0
0.2
0.4
0.6
0.8
1.0
100 microns austenite grain size
PEARLITE  w 
11 K/min
0.0
0.2
0.4
0.6
0.8
1.0
101 K/min
740
700
660
620
580
Jones & Bhadeshia, 1996
Temperature / °C

6.   11 K/min 101 K/min Temperature / °C
0.0
0.2
0.4
0.6
0.8
1.0
30 microns austenite grain size
PEARLITE 
11 K/min
0.0
0.2
0.4
0.6
0.8
1.0  w
101 K/min
760
720
680
640
600
Jones & Bhadeshia, 1996
Temperature / °C

7. Robson, Jones & Bhadeshia, 1996

8. Steel F (10Cr1MoV)
Robson & Bhadeshia, 1996

9. Baker & Nutting 2.25Cr1Mo Steel
Robson & Bhadeshia, 1996

10. NF 616
Robson & Bhadeshia, 1996

11. Driving force for M2X precipitation
Robson & Bhadeshia, 1996

12. Steel F (10CrMoV)
Robson & Bhadeshia, 1996

13. M2X precipitation
Robson & Bhadeshia, 1996

14. M23C6 precipitation
Robson & Bhadeshia, 1996

15. Laves phase precipitation
Robson & Bhadeshia, 1996

16. Robson & Bhadeshia, 1996

17. b a

19. Kasuya, Ichikawa, Fuji and Bhadeshia, 1999

20. Kasuya, Ichikawa, Fuji and Bhadeshia, 1999

21. 0.7
0.6
Prestrain
0.5
0.0
0.4
0.18
0.3
0.36
0.2
0.63
0.1
0.0
Singh & Bhadeshia, 1996
100
200
300
400
500
600
Time / s

22. 0.7
Prestrain
0.6
0.0
0.5
0.4
0.63
0.3
0.2
0.1
0.0
Singh & Bhadeshia, 1996
100
200
300
400
500
600
Time / s

23. Prestrain M of the alloy 400 350 300 0.0 0.2 0.4 0.6 s
Singh & Bhadeshia, 1996
Prestrain

24. o
500 C o
475 C
0.6 o
450 C o
400 C
0.4
0.2
0.0
0.0
0.2
0.4
0.6
0.8
1.0
Prestrain