1. Bengal Engineering & Science University
Neural Networks
Bengal Engineering & Science University

4. critical stress intensity
Charpy
fatigue
tensile
critical stress intensity
corrosion

5. Variables C, Mn, Si, Ni, Cr, Mo, V, Co, B, N, O…..
Thermomechanical processing of steel
Welding consumable
Welding parameters
Subsequent heat treatment

6. y x
Michael McIntyre

7. Variables C, Mn, Si, Ni, Cr, Mo, V, Co, B, N, O…..
Thermomechanical processing of steel
Welding consumable
Welding parameters
Subsequent heat treatment

8. Empirical Equations
y = a + b (%C) +c (%Mn)
+ d (%Ni) ....

9. y = a + b (%C) +c (%Mn)
+ d(%C x %Mn)

10. y = a + b (%C) +c (%Mn)
+ d(%C x %Mn)
y = sin (%C) + tanh (%Mn)

12. Hyperbolic Tangents

20. y A B x

21. GTA weld at 823 K (data from Nippon Steel)
600
500
400
300
200
100
20000
30000
40000
Life / hours
Cole & Bhadeshia, 1999

22. Cool, 1996

23. Cool, 1996

24. 600 °C
As-welded
700 °C
650 °C
Cool, 1996

25. Siemens
Mitsui Babcock
Nippon Steel
ABB

26. Thank you

28. Murugananth & Bhadeshia, 2002

29. Coalesced bainite
Keehan, Karlsson, Andrén and Bhadeshia, 2005

31. Nickel base alloy FT750dc
wt%

33. Tancret & Bhadeshia, 2002
1000
800
600
Yield stress / MPa
400
200
200
400
600
800
1000
1200
Temperature / °C

39. Yokota & Bhadeshia, 2004

42. Higher flow stress at lower temperatures
Greater uncertainty at lower temperatures

43. 800°C
Experiments needed
Silicon / wt%

44. Thank you