Download presentation
Presentation is loading. Please wait.
1
Predicting the Microstructure and Properties of Steel Welds
2
MULTIPASS ARC WELD L.-E. SVENSSON
5
100 µm
6
20 µm Barrite, 1982
11
Manual Metal Arc Weld 180 Amps 34 Volts 4 mm/s 200 °C interpass Manual Metal Arc Weld 180 Amps 34 Volts 4 mm/s 200 °C interpass
12
1 2 3 4 5 6 1. Fe-0.4C 2. Fe-0.4C-2Si 3. Fe-0.4C-1Ni 4. Fe-0.4C-1Mn 5. Fe-0.4C-1Mn-1Cr 6. Fe-0.4C-2Mn 0 1 2 3 4 5 10 10 10 10 10 10 Time / s 800 700 600 500 400 300 200 Temperature / C calculations
14
Barrite, 1982
18
5 µm Barrite, 1982
19
0.110.090.070.050.03 0.2 0.4 0.6 0.8 1.0 Carbon / wt % Volume fraction Allotriomorphic Widmanstatten Acicular Fe-1Mn-C wt % manual metal arc welds
20
Bhadeshia & Svensson
23
Charpy toughness Murugananth & Bhadeshia
24
7Ni 2Mn
25
7Ni 0.5Mn
26
7Ni 2Mn
27
7Ni 0.5Mn
29
Weld Shape - Stitch Weld at 2.26 kW Laser Output Laser beam K eyhole L aser beam F usion Z one
30
m w
31
Optically: mainly -ferrite some w-ferrite <5% martensite TEM: -ferrite much w-ferrite 155, 157 and 170 HV Mean Hardness: 161 HV Grain size 100 ±20 m 46% -ferrite 21% w-ferrite 30% acicular ferrite & bainite 3% martensite 168 HV Grain size 103 m Measured Calculated
32
Charpy fatigue corrosion tensile critical stress intensity
33
Variables C, Mn, Si, Ni, Cr, Mo, V, Co, B, N, O….. Thermomechanical processing of steel Welding consumable Welding parameters Subsequent heat treatment
34
Empirical Equations y = a + b (%C) +c (%Mn) + d (%Ni).... y = a + b (%C) +c (%Mn) + d (%Ni).... 1223
35
y = a + b (%C) +c (%Mn) + d(%C x %Mn) y = a + b (%C) +c (%Mn) + d(%C x %Mn)
36
y = a + b (%C) +c (%Mn) + d(%C x %Mn) y = sin (%C) + tanh (%Mn) y = a + b (%C) +c (%Mn) + d(%C x %Mn) y = sin (%C) + tanh (%Mn)
38
Hyperbolic Tangents
41
non-linear functions
44
Predict what the next two numbers are likely to be: 2, 4, 6, 8, …….
46
Brun, Robson, Narayan, MacKay & Bhadeshia
47
precipitates solid solution iron + microstructure 550 °C 600 °C Murugananth & Bhadeshia Components of Creep Strength, 2.25Cr1Mo
48
Cole & Bhadeshia
50
Cool, 1996
52
As-welded 600 °C 650 °C 700 °C Cool, 1996
53
Siemens Mitsui Babcock Nippon Steel ABB
54
Thank you.
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.