Evolution curves, for cold-worked pearlite in the steel, exhibited 2 stages at 100C. A single stage was observed at 400C for this material, and for tempered martensite at either temperature. The 2 evolution stages at the lower temperature were associated with traps with differing binding energies. The evolution of H at 400C was considered to be diffusion-controlled in both steels. The diffusion coefficients at this temperature were equal to 1.4 x 10-9 and 2.1 x 10-9m2/s in pearlite and martensite, respectively.
E.Strecker, D.A.Ryder, T.J.Davies: Metal Technology, 1975, 2[5], 236-7
Table 50
Diffusivity of H in Fe Alloys
C (%) | Mn (%) | Cr (%) | T (C) | Dlattice (cm2/s) | Doverall (cm2/s) |
0.055 | 1.5 | - | 640 | - | 1.0 x 10-4 |
0.055 | 1.5 | - | 410 | - | 7.6 x 10-5 |
0.055 | 1.5 | - | 270 | 1.0 x 10-4 | 6.6 x 10-5 |
0.055 | 1.5 | - | 105 | 3.9 x 10-5 | 2.7 x 10-5 |
0.055 | 1.5 | - | 55 | - | 3.1 x 10-6 |
0.055 | 1.5 | - | 20 | - | 2.0 x 10-6 |
0.003 | - | 5.58 | 640 | - | 1.8 x 10-4 |
0.003 | - | 5.58 | 545 |
| 1.4 x 10-4 |
0.003 | - | 5.58 | 450 | 1.8 x 10-4 | 1.1 x 10-4 |
0.003 | - | 5.58 | 350 | 1.7 x 10-4 | 9.9 x 10-5 |
0.003 | - | 5.58 | 250 | 1.0 x 10-4 | 5.8 x 10-5 |
0.003 | - | 5.58 | 200 | 7.8 x 10-5 | 3.5 x 10-5 |
0.003 | - | 5.58 | 120 | 5.2 x 10-5 | 3.0 x 10-5 |
0.003 | - | 5.58 | 103 | 3.9 x 10-5 | 2.3 x 10-6 |
0.003 | - | 5.58 | 80 | - | 7.0 x 10-6 |
0.003 | - | 5.58 | 50 | - | 2.3 x 10-6 |
0.003 | - | 5.58 | 30 | - | 1.8 x 10-6 |
0.73 | - | - | 650 | - | 9.9 x 10-5 |
0.73 | - | - | 395 | - | 7.5 x 10-5 |
0.73 | - | - | 350 | 1.0 x 10-4 | 5.1 x 10-5 |
0.73 | - | - | 310 | 1.0 x 10-4 | 5.1 x 10-5 |
0.73 |
| - | 250 | 8.9 x 10-5 | 6.2 x 10-5 |
0.73 | - | - | 210 | 8.9 x 10-5 | 6.2 x 10-5 |
0.73 | - | - | 155 | 7.8 x 10-5 | 4.9 x 10-5 |
0.73 | - | - | 60 | - | 2.0 x 10-7 |
0.73 | - | - | 44 | - | 5.2 x 10-8 |