1 Introduction
2 Model Description
2.1 Starting Structure
2.2 Ferrite Nucleation
2.3 Ferrite Growth
2.3.1 Non-overlapping of diffusion fields
2.3.2 Soft impingement
2.3.3 Hard impingement
2.4 Computational Procedure
Model Trans. | Domain Size (μm3) | Austenite Grains |
ρ
max (× 1015 m−3) |
\( \rho_{\hbox{max} }^{ - 1/3} \)
(μm) | Model Nucl. |
M
0 (× 10−6 m4 J−1 s−1) |
δT (K) |
---|---|---|---|---|---|---|---|
Phase-field | 45 × 45 × 45 | 12 | 0.17 | 18.0 | SNM | 0.24 | 0 |
12 | |||||||
24 | |||||||
0.35 | 18 | ||||||
0.38 | 24 | ||||||
Present model | 70 × 70 × 70 | 82 | 0.17 | 18.0 | SNM | 0.24 | 0 |
12 | |||||||
24 | |||||||
0.15 | 0 | ||||||
0.26 | 18 | ||||||
0.3 | 24 | ||||||
0.17 | 18.0 | CNT | 0.3 | 24 | |||
0.25 | 15.8 | 0.3 | 24 |
3 Results
3.1 Comparison Between the Present Model and the Phase-Field Model
3.2 Comparison Between the Simplified Nucleation Model (SNM) and the Classical Nucleation Theory (CNT)
3.3 Carbon Diffusion and Mixed-Mode Character
4 Discussion
f
α
|
δT = 0 K, SNM |
δT = 24 K, SNM |
δT = 65 K, CNT | |||
---|---|---|---|---|---|---|
E (μm) | SD (μm) |
E (μm) | SD (μm) |
E (μm) | SD (μm) | |
0.01 | 2.4 (1) | 0.0007 (3) | 3.2 (9) | 2.0 (9) | 2.9 (8) | 1.9 (8) |
0.05 | 4.2 (1) | 0.07 (2) | 4.6 (8) | 3.0 (9) | 4.3 (9) | 2.9 (7) |
0.25 | 7.1 (2) | 0.6 (2) | 6.7 (9) | 5.4 (9) | 6.7 (9) | 4.5 (6) |
0.50 | 8.7 (5) | 1.6 (4) | 8.0 (4) | 4.5 (8) | 8.3 (9) | 2.3 (5) |
0.89 | 10.5 (5) | 1.7 (5) | 8.4 (8) | 4.8 (6) | 9.0 (5) | 1.8 (4) |