Bengal Engineering & Science University Neural Networks www.msm.cam.ac.uk/phase-trans Bengal Engineering & Science University

critical stress intensity Charpy fatigue tensile critical stress intensity corrosion

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

y x Michael McIntyre

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

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

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

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

Hyperbolic Tangents

y A B x

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

Cool, 1996

Cool, 1996

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

Siemens Mitsui Babcock Nippon Steel ABB

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Murugananth & Bhadeshia, 2002

Coalesced bainite Keehan, Karlsson, Andrén and Bhadeshia, 2005

Nickel base alloy FT750dc wt%

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

Yokota & Bhadeshia, 2004

Higher flow stress at lower temperatures Greater uncertainty at lower temperatures

800°C Experiments needed Silicon / wt%

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